HEAVY OFFENSE
INTRODUCTION:
Heavy Offense, also commonly referred to as HO or Dual Screens Offense, is the most offensive style in Pokemon possible.
It has a simple concept: set-up screens or hazards, and then use Pokemon with similar counters on the team to quickly set-up and weaken the opponent's counters (often requiring many sacrifices) before easily sweeping through the weakened opposition. By following this simple concept, HO teams eliminate the need to switch, and thus, the need to predict. This makes HO teams the most reliable teams; however, this does not mean that HO teams are "mindless" at all. HO teams require possibly the longest long-term planning skills of any type of team.
Despite the time it takes to learn how to play HO successfully, HO is probably one of the most satisfying teams to play with - not only do they have very few "unwinnable" match-ups, they also end matches incredibly quickly and are, for the most part, unaffected by hax.
THE CONCEPT OF MUTUAL COUNTERS:
One of the most common fallacies that most beginners to Pokemon suffer from is the idea that all teams should be "Physical Wall / Special Wall / Physical Sweeper / Special Sweeper / Spiker / Rapid Spinner". While a team that has that form could be effective, it is hardly necessary to run such a team to be successful.
On HO teams, it is almost necessary to run either all Special or all Physical Sweepers. (The metagame is a lot more welcoming to Physical Sweepers at the moment.) This is because running sweepers of the same spectrum means that the Pokemon that wall your team are halved - an all Physical team will only have to deal with Physical Walls, and an all Special team will only have to deal with Special Walls.
The majority of Bulky Offense teams will only carry one Physical Wall or one Special Wall, and Stall teams will run three Physical or three Special Walls at most. This means that there is only one Pokemon on a Bulky Offense team must be killed for your team to be able to sweep, and it means that Stall basically starts out at a 6-3 disadvantage!
Although the previous statement was a gross oversimplification, it illustrates a very good point - by not mixing sweepers, it puts a lot more pressure on your opponent to maintain the health of a few Pokemon, while you can happily sacrifice all of your Pokemon just to weaken a few Pokemon because you are guaranteed a sweep if those few Pokemon are weakened or KOed.
A very good example of this idea of mutual counters is through a common HO core of SD Scizor and DD Haxorus. DD Haxorus is walled (and even then, not completely) by very few Pokemon; its main counter is Skarmory. By running SD Scizor, Skarmory will be forced to switch in to wall it, only to see that it will fall at the hands of a +2 LO Superpower. Even if Scizor dies to a Brave Bird, Skarmory will be weakened to the point of being unable to wall Haxorus anymore, and Haxorus will be able to sweep the opponent's team.
MOMENTUM:
In Pokemon, one of the most important (yet one of the hardest to define; see: Tomohawk) concepts is "Momentum". Momentum, is, most simply, control of the game. Although momentum is quite intangible, its effects are quite obvious - momentum is seen through weather control, hazard control, and, most importantly for non-weather HO teams, free turns.
Heavy Offense is built on the idea that the opponent should have no free turns; if the opponent has free turns then that means that they are not pressured enough and that they will be able to recover from your attacks - it also means that they might be able to set-up and sweep you. Additionally, HO thrives on having free turns - each free turn is a turn of set-up that gives another opportunity to weaken a wall or sweep the opponent's team.
However, it is not enough to have a free turn; it is important to capitalize on each turn, or else all the momentum will be lost, and the opponent will be able to respond to your attacks. HO is all about controlling momentum so that the opponent will not be able to recover to your attacks. Furthermore, you should be the aggressor, not your opponent. Your opponent should be forced into a defensive playstyle where they must respond to you, as that is the playstyle that HO thrives against.
HOW TO MAINTAIN MOMENTUM:
As talked about above, momentum is quite important. The question is, how do we maintain it? How do we not allow our opponents any free turns? The answer is simple; just keep on pounding at your opponent with attacks, and never let up. Never switch; to switch is to allow your opponent a possibly deadly free turn.
Obviously, it would be stupid to just keep attacking an opponent if your attacks do barely anything, as it would mean that your opponent could just set-up on you and sweep you; for example, attacking a Gyarados repeatedly with a Caterpie will just allow it to set-up to +6/+6 and sweep you. Therefore, it is essential while team-building to pick Pokemon that can threaten basically any Pokemon; it is almost impossible (and quite stupid) to set-up on a DD Haxorus as there is no Pokemon which Haxorus does not threaten - it is in your opponent's best interest to attack Haxorus.
Even if you do run into a situation where you might not be able to threaten the opponent' Pokemon (for example, you have a +1 Lucario with Close Combat / Extremespeed / Ice Punch in against a Bulky Gyarados), often times, it is beneficial to not switch and let Life Orb recoil take its toll; if you are at 15%, you can simply Close Combat twice of Close Combat + Extremespeed instead of switching; this way, you dent Gyarados while being able to switch at the same time.
After you sacrifice your Pokemon, you should be able to switch into another Pokemon that has a favorable match-up. This gives you a free turn to set-up while making sure that the opponent has had no free turns; you have maintained momentum.
PRIORITY:
Obviously, there will be some times that you will not be able to stop a Pokemon from setting up against you, or, alternatively, an opposing Pokemon is faster than all of your team and has a strong move that none of your Pokemon resist (for example, LO Latios or Specs Jolteon). Thankfully, the majority of these Pokemon are quite frail; therefore, it is possible to overcome these threats with the power of priority.
The two most common priority users seen on HO teams at the moment are Scizor and Lucario. Between the two of them, all threats should be revengeable.
Scizor @ Life Orb
Adamant
248 HP / 252 Atk / 8 Spd
-Swords Dance
-Bullet Punch
-Super Power
-Bug Bite
Scizor's powerful Bullet Punch allows him to revenge a huge list of threats - this list includes Terrakion, Scarf Tyranitar, Latios, Latias, Salamence, and Dragonite. Note that many of these threats require prior damage to be KOed by Bullet Punch.
Lucario @ Life Orb
Adamant / Jolly
4 HP / 252 Atk / 252 Spd
-Swords Dance
-Close Combat
-Extremespeed
-Ice Punch / Crunch / Stone Edge
Lucario's powerful Extremespeed allows him to revenge such threats as Tornadus, Scarf Rotom-W, Jolteon, and Starmie after prior damage.
LONG TERM THINKING:
As opposed to the HO of 4th Generation, 5th Generation HO has gained one major boon: Team Preview. Team Preview allows you to analyze the opponent so you can see which Pokemon you need to eliminate and what Pokemon you need to be careful of; this allows you to generate a plan of what you can sacrifice and what you need to keep alive. The main thing about long-term thinking is that by Turn One, you need a plan of how you will sweep the opponent's team, and you should be able to visualize how the end-game should be.
COMMON PROBLEMS WITH HEAVY OFFENSE:
Although HO is an incredibly good playstyle, it still has some obvious problems.
Dragonite is probably one of the most difficult Pokemon for HO to deal with; if the opponent gets it in with Multi-Scale intact, then it will most likely rip through your team as it will be able to boost up to +1/+1 and go on a rampage. As long as you have Stealth Rock and / or screens up, then this Pokemon shouldn't be too hard to deal with.
Naturally speedy Pokemon also hurt HO teams a lot; HO teams love to outspeed the opponent so that they can attack first, but fast Pokemon don't allow HO teams to do so. The main way to deal with these Pokemon is through powerful priority and through tanking hits under screens (or with naturally bulky Pokemon such as Tyranitar). However, despite these methods of dealing with them, fast Pokemon are one of the main reasons HO is so difficult to master.
Such "anti-metagame / gimmick" strategies such as Tailwind or Trick Room are possibly the hardest matchup for Heavy Offense teams. They complete deny the strategy of HO of outspeeding the other team, and, to top it off, Tailwind and Trick Room teams tend to have incredibly strong firepower with which to blow holes in HO teams. The best way to deal with this is to try and prevent Tailwind or Trick Room from being set up through use of Taunt, or, if this is impossible, to capitalize on the free turn you get by them setting up Tailwind / Trick Room and making them sacrifice their Pokemon.
MATCHUPS OF HEAVY OFFENSE IN FIFTH GEN:
Heavy Offense vs Stall:
This is probably Heavy Offense's most interesting match-up, in my opinion. The main focus of Heavy Offense is to eliminate the few walls and sweep; in matches against stall, defeating that key wall will allow you to win 100% of the time as you do not have to worry about being revenged. Heavy Offense should always win this, in my opinion, unless it is misplayed. DD Haxorus behind screens tends to be amazing at this; Stall teams absolutely have no check to Haxorus besides Skarmory or Ferrothorn, and they are both beaten by Haxorus if screens are up.
Heavy Offense vs Bulky (Rain or Sand) Offense:
You should win this almost as much as you win stall. The only variation is that these type of teams tend to run revenge killers, so it is important to use revenge killers as set-up after they revenge a Pokemon. SD Lucario tends to dismantle Bulky Offense single-handedly.
Heavy Offense vs Sun Offense:
This match-up is actually in the favor of Sun Offense, unless you run something like DD Tyranitar on your Heavy Offense team. Since sun teams generally hate Stealth Rock, keeping Stealth Rock up works very well in assuring your victory. Also, running Dragons on your team also helps as most Sun teams cannot handle +1/+1 Dragons.
Heavy Offense vs Volt-Turning Teams:
Volt-Turning teams are actually handled quite similarly to Bulky Offense. Strong Rock types tend to hurt Volt-Turning teams quite a bit, and generally the only Dragon check will be Scizor, so it is quite easy to over load it with strong Outrages.
Heavy Offense vs Heavy Offense:
This is a match-up that comes down to speed ties and prediction, basically. You can hope to win this through superior long-term planning, but it's really hard as you both will just be firing off attacks and, oftentimes, hoping that you win the speed tie. Remember that if you set-up that you will most likely win, and capitalize on that fact.