Not all battles are played with conditions favoring either player, and an experienced battler can easily influence the tide of battle through using battle conditions. Battle conditions are, simply put, effects that take place in battle in which the usual game mechanics are slightly changed—these changes can be temporary or permanent, and can benefit you or hinder your opponent directly. Battle conditions are an integral part of competitive Pokemon, and pushing the conditions you are playing under in your favor is almost as important as a superior team match-up.
Consider the Battle Arcade in the Sinnoh Frontier. Every battle you play a roulette-style game that determines these conditions during the battle. Each choice will have a different effect; some may lower the opponent's HP or poison the opponent's Pokemon - the choice may affect the player's Pokemon, the opponent's, or even the field. In a regular battle this problem does not exist, but in every competitive battle, you can recreate these advantageous conditions for yourself. While this may seem like too much of a hassle, it is an essential skill for all players to be able to understand and control these battle conditions, and to be able to use them correctly against opponents.
Entry Hazards are the simplest and most common battle conditions that you will run into. Their effect on the battle is also the most simple, damaging opponents every time they switch in (except for Toxic Spikes, which has a slightly different effect), and they are found on almost all teams, with offensive teams finding them useful to wear down walls to build up damage over time, and defensive teams using them to wear down the opponent by continually forcing their Pokemon to switch. The reason for their popularity is that they are more or less permanent, often being difficult to remove without hindering one's team, as offensive teams can lose precious momentum through that one vital turn that is spent clearing away hazards. Other reasons include the fact that they are quite quick to set up, and have an effect that can be exploited by almost any sort of team. While there are limits to the number of entry hazards you can set up, different types of entry hazards can be used in conjunction; the maximum number of entry hazards allowed on the field at any one time are three layers of Spikes, two layers of Toxic Spikes, and one layer of Stealth Rock.
Stealth Rock is far and away the most common entry hazard about. It is also the easiest to exploit, since it only takes one turn to set up to its full extent, which is useful for fast-paced offensive teams, and hits almost every Pokemon in the game for at least some damage. The amount of damage it does to the opposing Pokemon depends on how weak they are to Rock attacks. For example, if a Pokemon is neutral to Rock-type attacks, it takes 12.5% damage from Stealth Rock each time it switches in. Damage multiplication from its typing applies here as it would with a regular attack, as shown in the table below:
|Damage multiplier on Rock-type attacks||Damage taken from Stealth Rock|
|4x resistance (Lucario, Steelix)||3.125%|
|2x resistance (Hippowdon, Gallade)||6.25%|
|Neutral (Scizor, Blissey)||12.5%|
|2x weakness (Arcanine, Gyarados)||25%|
|4x weakness (Charizard, Yanmega)||50%|
As you can see, Stealth Rock has a fairly negligible effect on those who resist it, but it has a profound effect on those who are weak to it, so much so that the face of the metagame is visibly altered by it. Single-weakness Pokemon such as Arcanine and Regice are kept from being used to their full potential because of it, and staples such as Gyarados are just able to struggle through the limit to five switch-ins thanks to their natural bulk, independence, and sheer power. Pokemon such as Moltres and Articuno could otherwise be well-suited to filling some of the niches of standard play thanks to their typing, but the massive loss of half their health every time they switch in makes them much less usable without very large amounts of team support. There are very few teams that do not use Stealth Rock, so you should try to prepare for it as best you can.
When setting up Stealth Rock, the best strategy is usually to put it up early on in the game to maximize the overall damage output throughout the battle. The simplest way to get Stealth Rock up quickly is to use a very fast lead to set it up - the concept of the 'suicide lead'. Aerodactyl is a good example of this—he can lay down Stealth Rock before nearly anything else in the game can stop him thanks to his base 130 Speed, and can also use Taunt to stop any other lead trying to set up Stealth Rock at the same time. Azelf works in much the same manner, except that it has access to Explosion in addition to Taunt and Stealth Rock. The reason these are termed 'suicide leads' is because they are not designed to survive - their only purpose on the team is to set up Stealth Rock while preventing the opponent from doing so, which just goes to show how powerful Stealth Rock really is.
However, if you do not want to lose a precious team member for your support, never fear - there are alternatives. The most reliable option is using a bulkier Pokemon such as Swampert or Metagross as a Stealth Rock lead, enabling you to possibly switch out and return again later in the battle should you have an inferior match-up, and also allowing you to set up Stealth Rock again and again should it be removed the first time. The downside is that these Pokemon are very susceptible to Taunt, so are not guaranteed to get the job done the first time. If you do not want to run Stealth Rock on your lead, a support Pokemon can set it up if it gets an opportunity later in the game; Pokemon such as Gliscor and Hippowdon are notable options. Forcing switches through superior match-ups and momentum is usually a good way to rack up damage; however, for more direct influence, using "shufflers" such as Skarmory is another useful tactic. By forcing a Pokemon to switch using Roar or Whirlwind, not only are you scouting your opponent's team, but also racking up Stealth Rock damage against them. However, keep in mind that unfortunate switch can lead to an awkward situation, where someone like Heatran is matched up against Skarmory, and all your momentum is lost.
In other tiers, the story is much the same. In Ubers play, there are fewer viable Stealth Rock users to choose from. Deoxys-e is generally the best option for a fast Stealth Rock lead, as it is not only the fastest Pokemon in the game, but learns Spikes, Taunt, Light Screen, and Reflect in addition to Stealth Rock, making it the prime suicide lead for almost always getting the battle conditions in your favor. In terms of bulkier Stealth Rock leads, Groudon and Dialga are the most popular options thanks to their excellent overall bulk and movepools, while also hitting very hard in their own right. In Underused, there are fewer suicide Stealth Rock leads, and less availability for Stealth Rock in general, though there are quite a few common, bulky leads who can set it up early, such as Uxie, Registeel, and Omastar, the latter of whom also has access to Spikes and Toxic Spikes. Lastly, in Little Cup, the battles are a lot more fast-paced, often even more so than in Ubers play. Thus, there is little time for slower or bulkier leads to set up Stealth Rock, with some exceptions such as Hippopotas and Bronzor. Faster Stealth Rock leads in Little Cup include Diglett and Anorith, both of whom have the potential to outspeed the majority of Pokemon in Little Cup and set up Stealth Rock before being struck down. The damage from Stealth Rock in Little Cup is not usually game-changing, but it does do a valuable job in breaking Focus Sashes.
There is only one move in the game that can remove entry hazards on your side of the field—a curious attack called Rapid Spin. As it is an offensive move, it cannot be blocked by Taunt; however because it is a Normal-type move it will fail to have an effect when used on a Ghost-type opponent. Some teams will run Ghost-types such as Rotom-A simply to keep their precious entry hazards on the field; however, these Ghost-types are usually a valuable asset in any case, and are likely to be designed to last. These would be most commonly seen on stall teams; on offensive teams, Ghosts would usually be less long-lived, examples being Gengar in Overused and Mismagius in Underused, and included for different purposes than for blocking Rapid Spin. It is good to note that these Ghosts usually pose a serious threat to the spinners themselves in addition to simply blocking one move, though there are quite a few exceptions to this rule, such as Payback Forretress and offensive Starmie. The most popular Rapid Spinners in standard play are Starmie, Forretress, and Tentacruel, with Forretress seeing good amounts of play in Ubers as well, being able to abuse its high Defense and advantageous typing against a lot of the powerful Uber Pokemon, as well as being able to set up all three different entry hazards. In Underused, Rapid Spinners are fairly common, with Hitmontop and Donphan both popular choices, not only for Rapid Spin duties but also for utility elsewhere, with Claydol posing as another good choice. Hitmontop can also opt to specialize in Rapid Spinning through the move Foresight, which allows it to hit Ghosts with any move, preventing them from blocking Rapid Spin. Donphan can also imitate this strategy through the move Odor Sleuth. This tactic is unpopular, however, as it consumes so much of their utility in only one particular area. When playing against Stealth Rock, Rapid Spin is your only way of getting rid of them for good, and is essential if you have a very Rock-weak team. However, the best tactic for use is generally to ensure that most of your team either resists or is neutral to Stealth Rock—if you can carry out your team strategy well enough, Stealth Rock should not usually hinder you too badly. Despite being the most damaging move in the game, while preparing for it and using it well yourself should be a priority in building a successful team, Stealth Rock can be played around by most of the best Pokemon.
The second entry hazard you should be aware of is Spikes, which like Stealth Rock simply causes damage to the opponent's Pokemon whenever they switch in. However, unlike Stealth Rock, the damage taken by the opponent's Pokemon is not dependant on its typing, but rather how many layers of Spikes have been placed. One layer of Spikes is placed every time the move is used, and three layers can be put down at any one time, as shown in the table below:
|Layers of Spikes present||Damage taken from Spikes|
While Spikes does the same amount of damage to all Pokemon it hits, unlike Stealth Rock, it is less common regardless because of a few traits that make it less usable as an entry hazard. First and foremost, it takes three turns to achieve its maximum damage potential, and with only one layer the damage caused is negligible, whereas Stealth Rock takes only one turn to set up, making it ideal for a fast-paced offensive team. Also, Spikes does not affect Flying-types and Pokemon with the ability Levitate, whereas Stealth Rock hits all Pokemon for at least some damage, with the exception of Magic Guard Clefable, who is immune to all entry hazards regardless. Spikes is also available on far less Pokemon than Stealth Rock due to the latter's status as a TM move, making it widely available to many, while the former is restricted to level-up, and consequently only a few noteworthy Pokemon learn it. Lastly, Rapid Spin will remove all layers of Spikes when used, causing your set-up to be a waste of time. This is not so crippling for Stealth Rock users, who can quickly and decisively set up their entry hazards and, in the case of the bulkier ones, rinse and repeat, but Spikes users have to be cautious; bringing along a Ghost is even more essential than with Stealth Rock.
The two most popular Spikes users are Forretress and Skarmory, both of whom have high Defense and a great set of resistances, and coincidentally can both also set up Stealth Rock as well. Using two entry hazards together is a common tactic on stall teams in particular; Spikes are very rarely used without Stealth Rock as well. More offensive Pokemon that can use Spikes are generally limited to Roserade and Froslass, both of whom can usually get 1-2 layers up before going down, but are rarely used in that capacity owing to the general speed of play during an offensive game. Also, because of a peculiarity with Roserade's egg moves it can only ever have one of Spikes or Sleep Powder, limiting its effectiveness. In Ubers, Deoxys-s is the most common Spikes user, generally being used as a lead to get a layer of Spikes and Stealth Rock up before going down, putting its team in the most advantageous position for the rest of the match, although it does have the potential to be stopped. As previously mentioned, Forretress is also used in Ubers to set up Spikes, especially on the occasional stall teams. In Underused, Omastar acts very similarly to Forretress as a user of Spikes and Stealth Rock, though more commonly in the lead position. Qwilfish is the other popular Spikes user, being able to set up on popular Pokemon such as Milotic and occasionally Registeel. Spikes are far less popular in Little Cup, where the battles are very fast-paced and even using Stealth Rock is occasionally spurned in favor of an extra attack, and there are very few worthwhile Pokemon capable of using it, although Omanyte is able to use Spikes and can make a powerful Spikes lead in the right circumstances. When playing against Spikes, one should remember that it takes time to set them up. If you do not have a Rapid Spinner and they decide to be greedy, you can switch in a set-up sweeper such as Gyarados to abuse the free switch-in and set up, though beware of shufflers such as Skarmory.
Toxic Spikes are the last and most curious of all the entry hazards. Rather than causing damage when they switch in, they inflict the switch-in with the poison status, meaning that they will be taking damage whenever they are in play, rather than just whenever they switch in. They are a comparatively rare form of damage, but serve a purpose on teams dedicated to pinning other Pokemon down extremely well, such as those with bulky sweepers or stall teams. The table below shows the effect of Toxic Spikes:
|Layers of Toxic Spikes present||Resultant Condition|
|2 layers||Bad Poison|
As you can see, you can have a maximum of two layers at any one time, and the number of layers also dictates the Poison condition received. With ordinary poison, the afflicted Pokemon loses 12.5% of its health at the end of every turn, while with bad poison, the effect is cumulative; For example, on the first turn the afflicted Pokemon loses 6.25% of its health, and every turn after that the amount of HP lost is increased by that same amount, so on turn two 12.5% of HP will be lost, and on turn 3 18.75% of HP will be lost. Toxic Spikes are also unique in that they are not only removed by Rapid Spin, but are also removed by any Poison-type that hits them as it switches in. Toxic Spikes do not affect Flying-, Steel-, and Poison-types, as well as Pokemon with the Levitate ability. A Poison-type with the ability Levitate, such as Gengar or Weezing, will not be affected by the Toxic Spikes but will not absorb them either, as Levitate prevents it from striking them. All of the most popular Rapid Spinners are naturally unaffected by Toxic Spikes; Forretress by virtue of its Steel typing, Claydol by virtue of Levitate, Starmie by virtue of Natural Cure (healing the Poison status as it switches out), and Tentacruel by virtue of its Poison typing, allowing it to fulfill its job of Rapid Spinner without lifting a finger.
Of the Toxic Spikes users available in standard play, the most popular, such as Forretress and Tentacruel, are both Rapid Spinners themselves. Roserade is another good option, and could be considered more effective because it can use Toxic Spikes alongside Sleep Powder, something the Spikes user cannot do. In Underused, Toxic Spikes are more common, thanks to common Pokemon such as Drapion, Omastar, and Qwilfish learning the move, the latter two already mentioned for their utility with Spikes. Venomoth is another fast user of Toxic Spikes that plays almost identically to Roserade in Overused, incorporating Roserade's good Speed as well as Sleep Powder. Drapion, Qwilfish, and Venomoth can all also absorb Toxic Spikes on impact, making them good checks to Toxic Spikes as well. Nidoqueen and Nidoking are other common Poison-types in Underused.
In Ubers, while there are hardly any Poison-types to worry about, there are not many good Toxic Spikes users either, Forretress being the main exception. Despite this, it is well worth noting that Toxic Spikes are one of the foundations upon which Ubers stall is built on, with Forretress being able to easily set them up in most circumstances, and that they can be lethal against many of the most powerful Uber attackers, with almost half the tier left badly crippled by poison. It is also one of the reasons why Forretress is so invaluable to Uber stall teams, in that it is perhaps the best way to bring down hard-hitting attackers such as Groudon, Kyogre, and Mewtwo before they can cause very much damage. In Little Cup the story is similar to that of regular Spikes; a lack of reliable Toxic Spikes users coupled with a Speed-based metagame that usually makes them a waste of time. However, if attempting to stall in Little Cup, Toxic Spikes are one of the most important factors contributing to the success of the team, rather like the case in Ubers. The only really viable Toxic Spikes user in Little Cup is Tentacool, who can usually set up two layers on most common leads in order to allow the rest of the team to stall and annoy the opponent. From all this, you can see that Toxic Spikes are therefore much more suited to stall teams in general, as their cumulative damage effect makes them more suited to teams that wish to prolong the battle. They are an integral part of many stall tactics, including lesser-used ones such as sandstorm stall and hail stall, which you can read about in the next section.
The next category of battle conditions that should be considered is the weather, the different types being sandstorm, rain, sun, and hail. All four different types of weather follow the same pattern for setting up, either through a unique move or ability. When the corresponding move is used, a weather effect is generated, lasting a total of five turns, or eight turns with the unique corresponding item. If your Pokemon has an ability that sets up weather, the effects will take effect from the moment your Pokemon switches in, and will remain there until either the battle ends or a different weather effect is generated, since no two weather effects can be active at any one time. Unlike entry hazards, weather effects can change the game mechanics rather than simply causing damage, resulting in one or two types becoming far more powerful under the weather conditions, and thus when weather is used, many teams choose to base their entire teams around abusing the weather to the fullest, as it can be a very powerful tool in the right hands. There are also a number of moves and abilities that change capabilities when weather is active; for example, Thunder and Blizzard both change accuracies depending on the weather, a great factor to consider in environments where weather is likely to be prevalent.
The first and most common weather effect in standard play is sandstorm, since not only is it a lot more accommodating than other weather effects, allowing it to be used on many different teams, but it is also perhaps the easiest to set up in OU. This is because there are two Pokemon in the game that can set up an infinite sandstorm simply by switching in, thanks to their Sand Stream ability—Tyranitar and Hippowdon. This sandstorm will remain active throughout the battle unless replaced by another weather condition, which is unlikely to be seen in standard play unless the opposing team is based around that single strategy. Tyranitar is very popular on offensive teams, thanks to its decent defensive stats, monstrous Attack, and reasonable Special Attack; likewise, Hippowdon is good for stall teams, with a reliable recovery move in Slack Off and Sand Stream enabling it to whittle the opposing team down over time. While sandstorm can also be activated by the move Sandstorm, and the time it stays on the field can be increased by holding a Smooth Rock, this is much less efficient than using a Sand Stream Pokemon.
The most important effect that occurs while sandstorm is active is that all Pokemon that do not have a Rock, Ground, or Steel typing or the Sand Veil ability will lose 6.25% of their health every turn. While this may not seem like much on its own, it can have massive implications over a long time; for offensive teams, Sand Stream nullifies Leftovers recovery, making it harder for Pokemon without recovery to wall effectively. For defensive teams, the opponent's Pokemon are whittled down very quickly; factoring in Life Orb recoil, entry hazard damage, and other factors on top of sandstorm, a frail Pokemon will not be surviving for very long. Another important mechanic that changes during a sandstorm is that all Rock-types receive a 50% boost to their Special Defense stat, which is extremely useful as most Rock-types have a poor Special Defense stat or else a significantly lower stat than on the physical side, thus enabling Pokemon such as Regirock and Rhyperior to become near-impenetrable.
Sandstorm also has an effect on various moves that change their effects depending on the weather:
In addition to these moves, any Pokemon with the ability Sand Veil gets a 20% boost to its evasion stat during a sandstorm. Because of the remarkable prevalence of sandstorm in OU, the users of these moves are often given higher or lower status in battle because of it. While the users of Thunder and SolarBeam must rely on other moves of the same type, it is especially crippling to those attempting to take advantage of other weather conditions. For example, SolarBeam does not need to charge up during the sun weather condition, but does in sandstorm. Thus, if Tyranitar or Hippowdon were to switch in on the turn that the opponent used SolarBeam, the opponent would be locked in, be forced to use a 60 Base Power attack on the next turn and be unable to avoid a counterattack, almost always resulting in death. Thus, those moves aversely affected by sandstorm are almost never used in standard play, and if their users have no other alternative, they have to suffer for it. Tangrowth, Cresselia, and Arcanine all suffer on account of lacking "reliable recovery" despite having access to Synthesis, Moonlight, and Morning Sun, respectively. As they are unable to use the moves to their full potential, they are deemed less usable than Pokemon such as Skarmory and Celebi, who have access to Roost and Recover, respectively. In the same way, Sand Veil is a great help to Gliscor and Garchomp, both of whom often benefit from a lucky miss.
In other metagames, sandstorm is not so common. Although Tyranitar makes frequent appearances in Uber play, the sandstorm it brings is almost always cancelled out by the weather effects brought about by more common Pokemon, namely Kyogre and Groudon. Sandstorm is, really, almost nonexistent in Ubers, and therefore immunity to it or benefiting from it is certainly not as valuable there as it is in OU. Likewise, in Underused there is only one Sand Stream Pokemon available, Hippopotas, as both Tyranitar and Hippowdon are banned from Underused play. As such, sun teams can more freely use SolarBeam, and Synthesis, Moonlight and Morning Sun become classified as reliable recovery in the absence of harmful weather conditions. Hippopotas is usually more of a burden than a help in terms of the overall support it brings, even with the weather taken for granted, so is unlikely to be seen on most teams in Underused. Hippopotas is, however, usable in Little Cup, and is more commonly seen there than in Underused—the primary use of its sandstorm there is to break Focus Sashes, although it can also set up Stealth Rock, though its use aside from that is rather limited from a Little Cup perspective, a metagame which focuses heavily on offensive prowess. That said, sandstorm is a useful form of support in Little Cup, though not as commonly seen as in standard play.
Sandstorm is a very common battle condition in OU, as Tyranitar and Hippowdon are both very good Pokemon even without their weather abilities, so not all teams that incorporate one of these two Pokemon is by definition a true sandstorm team. Therefore, it is advisable that you make sure that at least some of your team is immune to sandstorm's damage—there are a great number of viable Steel-types, such as Scizor, Lucario, and Metagross, as well as Ground-types such as Flygon and Gliscor. The best defense against sandstorm teams is, in reality, to learn to put up with it, and try to keep momentum on your side, as short of running an opposing weather team, you will not be able to remove sandstorm or cripple it in that sort of way, and your team will be less than glad to see Tyranitar anyway.
The second most common weather condition is rain, which can be even more useful than sandstorm for driving forwards momentum on a team, as the way it helps teams is much more direct and straightforward than the more common weather condition. The reason for this is because there are far more abilities and moves that are affected by the rain than sandstorm, and the effects are easier to channel into a sweep; for example, Kabutops has the ability Swift Swim, which doubles its Speed as long as rain remains active, which is incredibly useful for a slower and more powerful Pokemon such as Kabutops. Not only that, but the rain also boosts the power of all Water-type moves by 50%, further increasing the Pokemon's offensive prowess as well, to such an extent that it is almost impossible to find a Pokemon that can take a hit from them. However, rain is less seen than sandstorm, not simply because it is less useful, but it is much less easy to set up. The only way to activate it outside of Ubers is by using the move Rain Dance, which summons rain for five turns, or eight if the summoner is holding a Damp Rock. There is usually very little difficulty in setting the rain up, as Rain Dance is available as a TM and is widely accessible to a variety of Pokemon, from bulkier ones such as Bronzong to extremely fast ones such as Electrode. However, the Pokemon in a rain team are essentially put on a timer, making it much more stressful to run than sandstorm. Even more crippling than the absence of a Drizzle Pokemon is the actual presence of not one, but two Sand Stream Pokemon available in standard—Tyranitar has only to switch in to almost completely ruin the strategy, and though it and Hippowdon are both weak to Water, their presence alone is enough to discourage an influx of rain teams in standard. Because of this, teams that use rain must almost always use it as their sole strategy, as it can be so devastating that there is little point not to capitalize on it in full. There are many abilities that activate when rain or another weather condition is stirred up, as shown below:
Of these abilities, all but Swift Swim are generally reserved for Pokemon that are usually quite weak even under rain or have no presence in standard, weakness or otherwise. For example, Hydration, an excellent ability, is confined solely to three Pokemon: Dewgong, Phione, and Manaphy. The former two have very poor base stats and have little usability in any tier, while the latter's base stats in conjunction with its ability are so powerful that it is considered an Uber Pokemon, and is thus banned from standard play. Swift Swim is the only ability that has any real competitive influence in standard, with powerful Pokemon such as Kabutops, Ludicolo, and Kingdra able to abuse the powerful bonuses granted to Water-types to become near unstoppable with the right support. Many of the moves already mentioned that are affected by sandstorm are also affected by rain, as shown below:
Many of these moves become far more useful when rain is in effect, most notably Thunder, which becomes a great option in the rain and is available to a lot of Water-type Pokemon, which works very well alongside their boosted STAB Water-type moves to take out opposing Water-types that may try to stop them, such as Vaporeon. The other notable mechanic change is the weakening of Fire-type moves, which, while having no real impact on the Water-type sweepers who are almost invariably resistant to Fire attacks anyway, is a real asset to many of the Pokemon that support rain teams by removing their weak links. Scizor is a tremendous help to rain teams for its ability to frighten away almost all the main threats to rain teams in general, not only being a threat to both Abomasnow and Tyranitar, both of whom can activate their abilities to dispel the rain immediately, but is also a big threat to Celebi and Blissey, both of whom threaten most rain teams. Both will often run a Fire-type move to deal with Scizor, which is where the rain comes in—by weakening the Fire-type move, Scizor can switch in relatively freely, Roost off the damage if it wants, and begin to threaten the opponent's team. It can even set up Rain Dance itself. Rotom-A is another good example, as it can abuse the weakening of Fire-type moves to beat its main foe, Heatran, as well as getting a boost to its STAB Thunder and possibly Hydro Pump, in the case of Rotom-W.
In standard, rain teams are not so common for lack of a reliable rain summoner. However, this all changes in Ubers play. Kyogre's Drizzle ability works identically to Sand Stream, except for the fact that it summons rain instead of sandstorm. Kyogre is practically omnipresent in Ubers—the rain it stirs up is a great help to almost every sweeper in Ubers, and this makes it even more desirable as a teammate, causing it to be more widely used. There is scarcely a battle in Ubers that does not involve a Kyogre of some description, and despite the presence of Groudon, the sun summoner, rain is a fact of life in every Ubers game. It is worth it to run Thunder in Ubers simply to take advantage of this fact, even if you don't use Kyogre yourself, although the most common use for Thunder in Ubers would be to hit Kyogre anyway. Of particular note alongside Kyogre are Palkia and Manaphy, the other two Uber Water-types. Palkia's Water-type STAB moves become frighteningly powerful, and when accompanied by Thunder and a Dragon-type STAB move, become a force to be reckoned with. In a similar vein, Manaphy can abuse its Hydration trait to the full extent, since it can use Rest, instantly recovering all the health it has lost, and then immediately be cured of the Sleep status, allowing it to set up while recovering all its health with ease. In Underused play, while Kyogre is still absent, Tyranitar, Hippowdon, and Abomasnow are all also banned, meaning that rain teams have very little to stop them rampaging through the tier beyond their own limited methods of setting the weather up. Not only that, but almost all of the best rain sweepers, such as Kabutops, Omastar, and Ludicolo, are allowed in Underused, and are thus able to cause even more havoc in a tier arguably less suited to dealing with them. In Little Cup, rain is also an important weather condition, and due to the fast-paced course of most games, can be an important asset for many sweepers, though the importance of priority in Little Cup can make the speed-based playstyle of rain offense irrelevant, as well as the ubiquitous Croagunk making life difficult for almost all rain sweepers.
When playing against rain teams, the thing to remember is that they have to keep the pressure on at all times, as they are on a timer to finish the job, and if you can force them back, they will have to waste precious turns regaining momentum again. On teams not built with rain teams in the highest importance, your best option is usually to sacrifice one of your Pokemon to allow the rest of your team to remain at full health, then to come in and threaten the opponent's Pokemon. Pokemon that usually threaten rain teams the most are those that resist their Water-type STAB, as firing off those powerful attacks is their main form of offense, though be aware that the better rain team users will often use their coverage attacks early on so as to catch your check before it can do any real damage. Pokemon such as Gyarados, Celebi, and Vaporeon are all bulky on both sides and all resist Water-type attacks; Vaporeon in particular even benefits from being hit by them thanks to Water Absorb. The sort of coverage moves they dislike are unfortunately often used on at least one rain team member; Gyarados hates Electric attacks, such as Thunder, Celebi dislikes Ice attacks, which are used on almost all Water-type Pokemon, and Vaporeon does not like Grass or Electric attacks, the former of which is usually carried only by Ludicolo. Be aware, however, that Vaporeon is very light and so the most common Grass-type move, Grass Knot, will do very little damage, and Electric attacks are often confined solely to Hidden Power Electric. Similarly, Celebi is not guaranteed to take over 50% from most unSTABed Ice Beams, although it will fall to an X-Scissor from Kabutops or Signal Beam from Kingdra.
Sun is a weather condition that acts very similarly to rain, but at the same time acts in completely the opposite way—where rain strengthens Water-type moves, sunshine weakens them. Like rain, it can only be set up in standard play by using a specific move, in this case Sunny Day, which generates the sun condition for the next five turns, or eight if the user holds the item Heat Rock. One of the main differences between Sunny Day teams and Rain Dance teams is that, while the Pokemon that excel on Rain Dance teams are almost always going to be Water-types, the sun condition is usually attributed to two types, Grass and Fire. While this may seem a good thing considering that it increases the variety of your team, it does in fact make Sunny Day teams comparatively weaker in general; while rain-oriented sweepers such as Kabutops get the boost to their abilities as well as their STAB moves, Grass-types tend to get a boost to their abilities in sunshine, but it is Fire-type moves which are strengthened. Not only this, but Tyranitar and other weather-changers are as much a threat as ever. Despite these shortcomings, Sunny Day teams are quite usable in standard and, like Rain Dance teams, do enjoy increased usage in other tiers. As with rain, there are a number of abilities that are activated when sunshine is active on the field:
Of all these abilities, Chlorophyll is perhaps the most useful for Grass-type sweepers. Pokemon such as Exeggutor and Tangrowth, who are usually quite slow, become very fast in sunshine thanks to Chlorophyll. These Grass-types also benefit from the boost to Fire-type moves, giving them the ability to bypass other Grass-, Steel-, and Bug-types that would usually wall their STAB attacks, such as Scizor. While Fire-types do not get the boost to the abilities that would so greatly help them, as a general rule they have very high-powered STAB moves that are boosted by the sunshine, usually backed up by solid attacking stats. Examples of this include Heatran, Magmortar, and Typhlosion, and although they are all generally weak to Water-type moves, the effects of the sunshine somewhat nullify this. Most of them can also use SolarBeam to take down Water-types, but have to be careful about Tyranitar switching in to ruin their fun. As with the other weather conditions, sunshine has its own effect on certain moves:
The merits of a couple of these moves in sunlight have already been discussed. However, while you may expect SolarBeam, Synthesis, Morning Sun, and Moonlight to be used significantly more under sunshine, this is not always the case. The latter three moves are all defensive, and unlike in sandstorm, where you have infinite amounts of playing time, in sunshine you are limited to eight turns, so there is no time to play defensively. SolarBeam is frowned upon in standard play, since if Tyranitar switches in on the turn you use SolarBeam, the effects of sandstorm on the move take place, meaning that you are locked into a weakened move, while Tyranitar gets a boost to its Special Defense stat and can easily annihilate you. Tyranitar is perhaps one of the reasons for Rain Dance teams being more popular than Sunny Day teams, since on Rain Dance teams Tyranitar must always be careful about switching in due to all the high-powered Water-type moves flying around, whereas in sunny day teams it has no qualms about taking a Fire-type attack, and also ruins SolarBeam users.
In Ubers, Groudon is capable of summoning everlasting sunlight thanks to its Drought ability. Groudon is not as common nor arguably as strong as Kyogre, however, since it does not always benefit from the weather it stirs, but if the ocean king can be taken out, Sunny Day teams can have a ball in the Ubers metagame, although they suffer from a lack of high-powered sweepers to take advantage of the weather and have to rely on lower-tier sweepers such as Shiftry. A popular tactic in double battles is to use Groudon and Cherrim together—Groudon's sunlight activates Cherrim's Flower Gift ability, which in turn patches up Groudon's weaker Special Defense stat while granting a great boost to its monstrous Attack stat. In Underused, much like Rain Dance teams, Sunny Day teams are quite popular, considering the lack of Tyranitar and the presence of pretty much all the sun sweepers regardless. Lastly, in Little Cup there are very few viable Sunny Day sweepers, with Bellsprout and Exeggcute being perhaps the most notable exceptions. However, as previously noted, rain and sun are often used for one individual's own benefit rather than the entire team's, and so rain sweepers are far more useful as variety in a team is not so great a concern, and having an individual with multiple talents is considered far more important.
The basic approach to dealing with Sunny Day teams is much the same as your basic method of dealing with Rain Dance teams, in that the power that they wield is often so great and comes so fast that you are best served by holding out until their allotted sunshine time has expired. As Pokemon on Rain Dance teams are usually going to be using Water attacks, the most common forms of offense on Sunny Day teams are usually Grass and Fire. One of the most common Pokemon in standard play, Scizor, is a great threat to Sunny Day teams, as not only does it have a 4x resistance to Grass-type moves, but it can scout out switches with a destructive U-turn and remove the frailer Grass-type sweepers with Bullet Punch. It will, however, faint to almost any Fire-type move and can be picked off by the Fire-types on your team. Heatran is another big threat to Sunny Day teams, as not only does it have a 4x resistance to Grass-type moves like Scizor, but also it is also immune to Fire-type attacks, and can pick off Chlorophyll sweepers easily with its STAB Fire Blast, which is boosted by the sunlight.
The last weather effect is hail, and the only one other than sandstorm to have an auto-weather summoner available in standard play, namely Abomasnow, with its Snow Warning ability. Like sandstorm, hail's most notable effect in battle is dealing 6.25% damage to every Pokemon on the field that isn't an Ice-type at the end of each turn; however, unlike sandstorm, it grants no boost to any stat of any type. Hail teams are not as popular as sandstorm teams, not only because it is much harder to find powerful teammates with a hail immunity in standard play, but also because Abomasnow is looked down upon as a Pokemon for its large number of common weaknesses and unimpressive base stats. However, you would be mistaken to suppose that hail teams are anything but a threat because of this. The following abilities are activated when hail is in play:
As you can see, there are fewer viable abilities that take advantage of the hail, and even those that are useful are usually confined to a select few relatively unusable Pokemon. Another unfortunate circumstance is that there is no hail equivalent to Swift Swim or Chlorophyll, meaning there are no hail sweepers that get a significant boost from the weather besides the extra damage. Most hail teams are therefore either partly or entirely defensively based, which is not easy to successfully build given that the only Pokemon immune to hail are Ice-types and the Clefable family, who are not the best defensively, not only having a weakness to Stealth Rock but also a weakness to common Fighting-, Fire-, and Steel-type moves, the latter of which is notable due to the omnipresence of Scizor with its infamous Bullet Punch. However, hail stall teams can still be very potent, thanks to some of the Pokemon available. Walrein is the most well known hail-abusing tank, able to come in and set up an infinite stream of Substitutes by alternating between Protect and Substitute, recovering 12.5% of its HP every turn thanks to Ice Body in tandem with Leftovers. This chain will last 32 turns, by which time the opponent will have taken 200% damage from the hail overall, so if your opponent's team has no Leftovers themselves, no recovery moves, and keeps its Pokemon in trying to KO Walrein, the opponent will lose two Pokemon to hail damage alone. This extends to even more damage if Walrein has Toxic Spikes support from a Pokemon such as Tentacruel, who, though lacking hail immunity, can set up Toxic Spikes, remove the opponent's Toxic Spikes just by switching in (which can be crippling to hail teams in general if not removed), and Rapid Spin away Stealth Rock and Spikes.
Bulky Water-types, such as the previously mentioned Tentacruel, are helpful to cover the weaknesses of the Ice-type core—Tentacruel in particular resists both Fire and Fighting attacks and is a good counter to Mixed Infernape, a big problem for hail teams, as well as having the benefits already mentioned. Water-types are also helpful to take on Tyranitar, a serious bugbear for most Ice-types, as well as being able to dispel the hail with Sand Stream. Tyranitar is a much bigger issue for hail teams than most rain or sun teams, as they usually have at least their STAB moves to fall back on when Tyranitar switches in, whereas Tyranitar is not much phased by most Ice-type moves and can attack back with STAB super effective Stone Edge. Bear in mind, though, that although many popular Ice-type Pokemon on hail teams, such as Mamoswine and Walrein, have secondary STAB moves that cover Tyranitar, you should be aware that most hail teams should try to carry an adequate response for it. There are also a few moves that change their effects when hail is active on the field:
Although there is no boost to Ice-type moves in general, Blizzard's increased accuracy is a godsend for offensive hail teams as well as defensive ones. No other weather condition increases the viability of a move so much that is the same type as the type most commonly associated with; rain boosts the power of Thunder, which does not gain STAB on most Water-types, sunshine boosts the power and removes the charge-up turn of SolarBeam, which is considered unusable because of Tyranitar, and sandstorm has no partner moves. Blizzard, on the other hand, is a massive help to almost all Ice-type and even non-Ice sweepers, given the great power it can achieve from the most powerful sweepers, and it is not rendered entirely unusable by Tyranitar. Glaceon has a huge base 130 Special Attack stat, and with Choice Specs its Blizzard hurts almost anything that tries to switch in. Glaceon also has the ability Snow Cloak, occasionally allowing it to survive an attempted revenge kill. Mamoswine also has Snow Cloak, and can use Blizzard to beat Skarmory, its most common counter, as well as having a great Attack stat and STAB Earthquake. Froslass is the only other fully evolved Pokemon with Snow Cloak, and it can abuse its great Speed to set up Spikes, as well as having a very powerful Blizzard at its disposal.
Other Pokemon are helpful for coverage purposes even if they don't have a hail immunity—Rotom-F has access to Blizzard as well as STAB Thunderbolt for a combination resisted only by Magnezone, Lanturn, and Shedinja, while also being a great counter to Scizor, who can be extremely troublesome for hail teams in general. Starmie could be seen as the offensive counterpart to Tentacruel, having great Speed and Special Attack, decent bulk, and resistances to Fire and Fighting, as well as access to STAB Surf, Blizzard, Thunderbolt, and Rapid Spin.
In other metagames, as with sandstorm, hail teams are not so common. In Ubers play, although Abomasnow occasionally sees use for its ability to hit all four of the other weather summoners—Kyogre, Groudon, Hippowdon, and Tyranitar—for super effective damage on their weaker side with one of its high-powered STAB moves (Blizzard for Groudon and Hippowdon, Wood Hammer for Kyogre and Tyranitar), it is usually considered too weak and too slow as a Pokemon to be used in Ubers often, and when it is, it is usually overshadowed by the omnipresent Kyogre and Groudon. In Underused play, although Walrein is still available, Abomasnow and Froslass are not, meaning that most hail teams are thus stuck with Abomasnow's weaker pre-evolution, Snover, to set up hail. Hail teams are, however, more common there than sandstorm teams, as the potential for creating a successful hail team is much greater. In Little Cup, Snover is also available, though there are few viable Pokemon in that tier that can take advantage of the weather, and generally Snover is better at simply abusing the hail itself.
As sun teams are similar to rain teams, so hail teams are considered similar to sandstorm teams. Hail can be extremely damaging over time, especially when your opponent is trying to stall you out with Walrein. The best thing to do is to keep your Fighting-, Fire-, and Rock-type attacks primed, so that you can push past the common Ice-types and score kills. Also remember that hail teams are almost never mono-Ice, and will almost always include at least two Pokemon for support purposes, such as bulky Water-types, and will also usually carry a good check for Tyranitar. In general, play as you would any other stall team, but keep an eye on your team's health, as it can disappear faster than you might think.
The final type of battle conditions that you will come across when battling are commonly known as arena conditions. These are like entry hazards in that they can be stacked on top of one another, and two different sorts can be active at the same time, but are also like weather effects in that they are only active for a finite amount of time, and also change the fundamental game mechanics. As with weather, these changes can be capitalized upon to benefit your entire team. However, unlike weather effects, these changes are rarely associated with a single type or types, meaning that the diversity of your team can be much higher while still taking full advantage of the arena condition itself. To put into perspective, the majority of a Rain Dance team is highly likely to be Water-type, as they are the ones that benefit most from it above all others, whereas there are a whole plethora of viable Pokemon that benefit from most arena conditions in equal measure. Arena conditions do not, however, have the effect of most weather in extremely high support, as they do not increase the power of any moves or convert ordinary Pokemon into monstrous sweeping machines, but rather only change one or two features of gameplay at most, which balances out the diversity in team structure. Weather is, however, usually considered more usable as support than arena conditions, not only because of sheer power being more practical for a team on a timer than overall diversity, but also because weather is comparatively more easy to keep on the field—not only are there permanent weather summoners available for use, but there are also special items that increase the precious time allotted for sweeping available to all weather teams, a luxury not available to those using arena conditions, with the exception of dual screen users.
By far the most common arena conditions are Reflect and Light Screen, which together make an impressive combination that allows a good number of strategies to develop. Although they are technically two moves, they are very easily used in conjunction and, despite the loss of two or more turns in setting them up, they can be extremely beneficial to any team. Their effect in battle is very simple; Reflect halves the damage of all physical attacks dealt to your team, and Light Screen does the same to special attacks. By using them both, you are protected at both ends, and the risk that the opponent's team poses to yours is greatly lessened. Their popularity is further enhanced due to the fact that they are the only arena conditions that can be extended via the use of a unique item, in this case Light Clay, which if held by the user of Reflect or Light Screen raises the number of turns that the effects remain in play from five turns to eight turns. While both moves are available to a very large pool of Pokemon, the combination of the two is generally restricted as a rule to Psychic- and Ghost-types, although there are some exceptions to this, such as Forretress and Magnezone, which means that your support Pokemon are likely to be very susceptible to Dark-types, as well as Pursuit, making sure that they do not try the strategy again. Of course, Reflect does partially remedy this, but the fact still remains that the dual screens will not always be set up more than once.
Dual screen support, as it is known, is quite interesting among arena conditions in that it does not require extensive team specialization in order to fit into a strategy, which is one of the reasons for its great popularity. The Pokemon that benefit most from this kind of support, as with rain and sun teams, are fast, powerful Pokemon with high damage potential, as your team is on a timer of eight turns to complete the strategy. Although the effects of screen support are primarily defensive, you can use them to your advantage with Pokemon that can boost their offensive stat of choice relatively quickly, since they are protected by the screens, and then attempting to sweep with the extra security of their enhanced defenses. Lucario is a great choice for a set-up sweeper, as it can boost its Attack stat easily with Swords Dance and cause massive damage to a great portion of the Overused metagame with its wide coverage, and while its defensive stats are not spectacular, it does benefit from resisting both Bullet Punch and Pursuit, and has no really crippling type weaknesses. On the special side of things, Azelf and Porygon-Z both have access to Nasty Plot as well as great all-around coverage, and benefit from the screens to lessen slightly their shared weakness to priority. Belly Drum Pokemon such as Charizard and Linoone also find it easier to set up under these conditions, given that there is now a lot less worry about the loss of health from Belly Drum.
One of the more cunning strategies sometimes employed is the use of dual screen Uxie, who not only has good defensive stats and Speed, allowing it to usually set up both Screens with ease, but also a hidden surprise: the move Memento. Usually looked down on in favor of Explosion, Memento does not cause great damage to a foe when used, but instead drops the foe's Attack and Special Attack by two stages, an effect which is immediately neutered by switching out the Pokemon in question. However, its great value on Uxie is that it does leave the opponent alive—with both screens up and both offensive stats halved, your opponent's Pokemon is a sitting duck, and easy prey for most boosting Pokemon to set up on. In Ubers, Latios can also employ exactly the same strategy with the benefit of greater Speed. Azelf and Alakazam are both faster users of dual screens, and can also use Taunt to stop most attempts to pseudo-haze them out, and both Azelf and Uxie can also set up Stealth Rock if need be, as well as using U-turn to avoid attempts to Pursuit them. Another similar strategy that is quite popular is using a simple Baton Passer in order to set up a powerful Pokemon without great boosting techniques of its own, such as Heatran or Metagross. A bulky, fast Baton Passer such as Gliscor can pass Swords Dance or Rock Polish boosts, or both, under cover of the screens, to the receiving party. Gliscor also has access to Taunt to stop attempts to Taunt or pseudo-haze from others. Although this wastes more screen time, the overall benefit is often enough to cover the cost, especially with the great boosts granted to the receiver.
As previously mentioned, these strategies are quite susceptible to Taunt and pseudo-haze attempts, and if you can counter attempts to pull the strategy through and break the chain, they have a tendency to break up before they can cause your team any serious woe, though they are still a force to be reckoned with. It is usually a bad idea to attempt to Pursuit a foe, especially if you are Choice-locked, as that basically constitutes a free opportunity for Lucario to come in and make your life hell. As for when the screens are already up, the only ways to remove them prematurely is either by using the move Brick Break, which will instantly destroy any screens up—including if the foe is a Ghost-type—or to use Defog, which is less helpful as doing so will also remove all the entry hazards that you yourself have set up, and has no other real competitive applications. If you can kill the set-up Pokemon (which should not be too hard as they will usually take a lot of damage setting up anyway) and ride out the eight turns, which are not always as long as you may think, you should be all right. Just be careful if you are up against a sweeper that you cannot check outright.
In other tiers, dual screens are also fairly common, as Deoxys-S in Ubers, the fastest Pokemon in the game, is able to set up the screens, and is also able to set up Stealth Rock or Spikes if need be, making it often very easy to set up extremely threatening sweepers such as Rayquaza or Groudon from behind the screens. Deoxys-S also has access to Taunt, to stop most pseudo-hazers from stopping the support. Latios is also a great choice, being able to mimic Uxie's dual screen Memento set with even more success, thanks to its higher Speed. In Underused, there are a lot of good dual screeners available as well, with bulkier users such as Claydol and faster ones such as Alakazam seeing a lot of use, as well as the aforementioned Uxie. Dual screens are less common in Little Cup, since as a rule Pokemon do not have the time to set up to that extent, but bulkier Pokemon such as Bronzor can execute the strategy to a fair degree of success, and allow dangerous Pokemon such as Dragon Dance Dratini to set up and charge through the opponent's team.
Trick Room is another curious arena condition which changes game mechanics in a relatively simple way, but in a way that vastly changes how the game is played. When Trick Room is active on the field, normal turn order is reversed—in other words, the slower Pokemon will move first, although normal move priority remains the same. This allows a game style similar to that of Rain Dance or Sunny Day teams, where you are given a finite amount of time to take full advantage of conditions in your favor. Although Trick Room does not power up Pokemon to the extent that rain or sun does, it does have a few notable advantages as a play style. Firstly, the Pokemon that most benefit from the condition are slow but hard-hitting Pokemon, and there are a number of Pokemon of almost every type that fit this criteria, usually allowing for a more balanced team than heavy rain offense.
While this may be seen as an advantage, the loss of serious offensive power that comes with weather really hurts Trick Room as a strategy, since even the most powerful of bulky offensive Pokemon cannot really emulate the direct power of rain and sun teams. The extra diversity found in Trick Room teams cannot really compensate for this, and indeed is not that much of an asset, since Trick Room teams are restricted in the same way that weather teams are in that they have a limited amount of time to abuse the advantageous conditions, and therefore cannot afford to waste time switching often when matched up unfaourably. Not only that, but Trick Room cannot be lengthened by holding an item when the move is used, unlike with weather and Dual screens, so your time for sweeping is essentially restricted to only four turns, or five turns if you count the turn directly after the move is used, when you should be switching to your sweeper. There are other problems when using Trick Room as well—it has a priority of -7, meaning that any other move in the game, no matter how fast the Pokemon using the move, will go first, and therefore you cannot simply have a very fast Pokemon set up quickly before the opponent can Taunt you (unlike with Rain Dance). Furthermore, almost all Pokemon who can use Trick Room are part Psychic- or Ghost-type, and of the nine Pokemon that are not, Dialga, Palkia, and Arceus are banned from standard play, while Stantler, Spinda, and Kecleon are barely usable even in Underused, which leaves Porygon2, PorygonZ, and Smeargle. It is very likely, therefore, that you will be forced to use Pursuit-weak Trick Room summoners, a similar problem to that of dual screens, except that the problem is even more relevant for Trick Room teams; without the protection of the screens, it is likely that your setup Pokemon will not last very long. Thus, it is recommended that you prioritize bulk when deciding on a Trick Room summoner, and low Speed will become an asset when you have successfully set up the condition. Pokemon such as Uxie, Dusknoir, and Bronzong are of particular note.
As previously mentioned, the Pokemon who flourish under Trick Room are those with very low Speed but very high offensive stats, and the potential to do a great deal of damage in a limited amount of time. Chief among these are slow and bulky Rock- or Ground-types such as Rhyperior, Rampardos, or Marowak. Generally, however, your team should work well assuming that you pick well, as there are many Pokemon available with below-average Speed, such as Metagross, Tyranitar, and Heatran, who all function well under Trick Room and are powerful enough to gain the upper hand over the opponent. While it may be tempting to run several of the very strong Rock-types available, remember that Trick Room does not affect move priority, and thus moves such as Bullet Punch, Aqua Jet, and Vacuum Wave are all troublesome for frailer Pokemon such as Rampardos. Including slower priority users in your team, such as Breloom or Scizor, is also advisable, as when you are unable to maintain Trick Room for your team you will need some way of beating faster Pokemon, especially if your Pokemon are designed to be as slow as possible. Special or mixed sweepers such as Clamperl and Octillery are also advised. The diversity of viable Pokemon is staggering, and you will rarely see two Trick Room teams that are overtly similar.
Trick Room in Underused is not altogether different from that in standard, as with weather teams, since a good number of those Pokemon usually seen on Trick Room teams in standard are still available in the lower tiers. With less opposition to them than in standard, Trick Room is thusly more popular in Underused. However, the much higher reliance on priority moves, and altogether higher usage of their users such as Azumarill and Hitmontop means that the less bulky sweepers will have an arguably tougher time in this environment, which is significant when you consider the absence of bulkier Trick Room sweepers such as Metagross and Heatran from Underused. When using Trick Room in Ubers, a horde of Trick Room summoners become available for use, given the heavy Psychic and Ghost concentration of the Uber Pokemon, such as Deoxys-D and Dialga. The chief difference in this tier is that it is heavily based upon Speed, and thus you would expect Trick Room to be especially potent a strategy here. However, this also means that you will rarely be able to afford the turns required to be switching in addition to setting up Trick Room, so in this environment pulling off Trick Room successfully takes a lot of skill and a fair bit of luck as well. You do get the advantage of being able to abuse the power of slower Uber powerhouses such as Kyogre and Groudon. In a similar vein, Little Cup is also extremely Speed-based; however, it is also heavily reliant on priority, making Trick Room here a mixed bag of sorts. If you can set it up successfully, Pokemon such as Munchlax can ruin opposing teams, and there are viable options in Bronzor and others to set it up. The turns required, however, can cost you greatly.
The only way to remove Trick Room prematurely is to use Trick Room yourself, which is not viable as a strategy. Trick Room sweepers rarely have the power of rain or sun sweepers off the bat, and as such can usually be countered or checked by the appropriate Pokemon. It is also worth noting that Trick Room has a much shorter lifespan than weather, and thus most Pokemon can be stalled out before they cause serious trouble. However, it is worth noting that these Pokemon still pose a great deal of a threat even outside Trick Room, possibly more so than for rain team sweepers. A Pursuit-user can usually remove the setup Pokemon to stop them repeating the trick, though any reasonably hard-hitting attacker should do just fine. Anything that the Trick Room Pokemon struggles against can get in and start dealing damage.
Lastly, Gravity is yet another interesting arena condition, which like Trick Room has limited longevity yet makes an intriguing team strategy when played correctly. It has several effects, some of which are of little relevance, but most of which are extremely useful. The first effect is that all Pokemon are deprived of their Ground immunities if they have them, meaning that a Pokemon such as Rotom-a becomes weak to Ground-type attacks, as well as being susceptible to Arena Trap and Spikes. This does not mean that the Flying-type is removed, as per Roost's side effect, but instead that the Ground immunity alone is removed. For example, Spikes will hit Flying-types, and Stealth Rock's damage remains the same. The second effect is that all moves have their accuracy increased by 67%; thusly all moves of 60% accuracy and above will always hit. This is enormously significant as it means that powerful moves such as Blizzard and Thunder have renewed viability. Other, less relevant effects include the inability to use moves such as Bounce and Fly that require lift-off. Gravity can be incorporated into both offensive and defensive teams, as it has particular merit for both. With defensive teams, the entry hazards Spikes and Toxic Spikes become much more viable as they now hit all Pokemon, enhancing the basic principles of the stall team in return for turns wasted to attain the effect, while offensive teams greatly value not only the greatly increased potency of Earthquake, but also the improved move accuracy, allowing much more powerful moves to be used. Dugtrio is also more powerful here as it can successfully trap and remove such Pokemon as Bronzong, Skarmory, and Rotom-a that oppose you.
As Gravity is available as a move tutor, there is a fair diversity in Pokemon that can set it up, and the problem of Trick Room in the majority of these being Ghost- or Psychic-type is rarely a nuisance here. Blissey is most prominent among them, easily being able to come in on special attackers to set up Gravity. Forretress is another common choice on defensive teams, with the added benefit of being able to set up all three entry hazards. Bronzong has solid defensive stats on both ends and benefits from a very accurate Hypnosis in Gravity, allowing it to generate free turns for its team. Offensive teams also have options such as Jirachi, Starmie, and Metagross for setting up Gravity. It should be noted that Gravity has the standard priority, meaning that a fast Pokemon such as Alakazam in the lead spot can easily set it up before it is struck by Taunt.
When building your team, you will want to take full advantage of the unique effects provided by Gravity. On defensive teams, this means primarily the enhanced effectiveness of entry hazards. Skarmory is a good example of this, as despite the lack of a Ground immunity, it can set up both Spikes and Stealth Rock, as well as racking up damage through Whirlwind. Hippowdon is also helpful as it can set up Stealth Rock, shuffle the opponent's team with Roar, and attack back with the more effective Earthquake under Gravity. It is also recommended that you include some Ground-type resistances on your team so that your opponent cannot take advantage of Gravity as well—Celebi is a good choice for its overall durability. On offensive teams, the main advantage created is the increased accuracy of moves and potency of Ground-type moves. Of particular note here is that the EdgeQuake combination of Stone Edge and Earthquake becomes completely unresisted, as well as Stone Edge's shaky accuracy being greatly improved, meaning Pokemon such as Tyranitar are much harder to stop. Mamoswine's STAB combination is also unresisted in Gravity, and thus it becomes a very great threat as well. Other Pokemon that rely on moves with poor accuracy, such as Heracross, who needs Megahorn and Stone Edge, and Gengar, who needs Focus Blast and Hypnosis, also benefit from Gravity. Also available are those Pokemon that can potentially use high risk moves such as Thunder and Blizzard, such as Starmie, since in Gravity the risk is removed. A Ground resistance is helpful here too; for this reason, Pokemon such as Torterra and Shaymin become viable options.
In other tiers, Gravity enjoys very little use. In Underused, many of the bulkier setup Pokemon are illegal, such as Blissey, Forretress, and Bronzong, so you will have to make do with Pokemon such as Registeel, Regirock, and Clefable, who are more than capable of performing adequately. There are, however, fewer Pokemon available to abuse the effects of Gravity, or at least that perform to a significantly better standard when under its effect. Aggron can abuse a 100% accurate Head Smash in tandem with Earthquake for an unresisted combination, while both Venusaur and Tangrowth benefit from a 100% accurate Sleep Powder and Power Whip, the latter also gaining the effect on Stun Spore, and also resisting Earthquake. Rhyperior also benefits from the effects thanks to the more potent Stone Edge + Earthquake combination. As previously mentioned, there are many Pokemon in Underused that can set up Gravity, and quite a few that can work well on Stall teams. Omastar can reliably set up any entry hazard, while Drapion can imitate Skarmory by setting up Toxic Spikes and then shuffling with Whirlwind. Donphan is also a good choice, being able to use Stealth Rock, Roar, and Rapid Spin in addition to abusing its STAB Earthquake and base 120 Attack stat. As with Trick Room, there are a vast number of Uber Pokemon that learn Gravity, such as Giratina, Dialga, and Deoxys-D, meaning that Gravity is not always a wasted strategy in Ubers; however, the setup turns required mean that the advantage gained for your team overall is only slight at best, and not even extreme powerhouses such as Groudon and Garchomp can take full advantage of the effects. In Little Cup, Gravity is rarely seen, as with Ubers in that the overall benefit does not equal the pains required to gain them, and though it can be helpful for Pokemon such as Cranidos and Staryu, most of the Pokemon that can set up Gravity are more often seen in other occupations.
Playing against Gravity is much like playing against any other arena condition in that it will only be around for a finite length of time, and if you can stop the individual Pokemon on the Gravity team, you should have very little trouble in dispelling the assaults for long enough to stage a counter strike. It is important to note that Gravity Pokemon are not particularly awful outside of Gravity, and do not have the unfortunate side effect of other condition teams in that they tend to perform to a sub-par degree in ordinary battle conditions, so play the team as you would most other teams, but be sure to take advantage of when the opponent is forced to set up Gravity again, as this is a good time to take advantage of the state of affairs and strike back.
The significance of all battle conditions in the formation of the competitive game is remarkable—while it may seem tempting to ignore them and play at your own game, the fact remains that nothing can then stop your opponent from taking the high ground to their own liking, and giving themselves a far higher chance of victory because of it. Like it or not, the game can and will be altered in the way it is played by the players, and it is your responsibility to know and act accordingly to make sure that you attain superiority in this field—doing so will drastically increase chances of victory, and while there is a lot of luck involved in coming out on top, knowing what to do will make the task far easier to face when it comes.
If you would like to know more about the conditions, strategies associated with them, team construction, and usage in practice, these excellent guides should be able to answer any of your questions.