Not so Itsy-Bitsy Spider
* Water Bubble prevents burns, halves Fire-type moves' damage, and doubles the power of Araquanid's Water-type moves. Put all these together with Water-type STAB, and Araquanid is going to deal serious damage even to Pokémon that resist Liquidation, and its offensive power cannot be easily hindered.
* Impressive Special Defense lets it tank strong hits, and even some super effective ones; for example, Nihilego's Power Gem after a Beast Boost only has a 50% chance to OHKO.
* Its low Speed lets it perform very well under Trick Room.
* Low offensive stats leave its other moves noticeably lacking in power.
* It's tough to be a Bug-type in a metagame with Tapu Koko, Kartana, and Tapu Fini, which can all easily counter it.
* Araquanid is rather easy to predict, as it only has one viable set.
name: Attacking Arachnid
move 1: Liquidation
move 2: Lunge / Toxic
move 3: Wide Guard
move 4: Protect
item: Waterium Z
ability: Water Bubble
nature: Brave / Adamant
evs: 252 HP / 252 Atk / 4 Def
ivs: 0 Spe
* Liquidation provides practically all of Araquanid's offensive presence, dealing 3x damage from STAB and Water Bubble alone and having a chance to lower the foe's Defense in the process.
* Lunge makes it harder for physical attackers to do their job by lowering their Attack.
* Toxic helps against bulky Pokemon like Gastrodon and Porygon2. It can also wear down Tapu Fini if you have another Terrain setter on your team.
* In general, the second slot should be filled with a move that lets Araquanid do whatever you need it to do.
* Wide Guard protects the team from spread moves, and is useful for Araquanid in particular to evade Rock Slide damage.
* Protect lets Araquanid survive one turn of damage and potentially stall out undesirable field effects like Hail or Electric Terrain. While Araquanid is protected, it can let a teammate set up, say, Trick Room so that it can dish out damage at high health the next turn.
* Maximum HP investment lets Araquanid survive against all kinds of attackers as long as possible, and 252 Attack EVs and a Brave nature let Araquanid hit as hard as possible.
* A Brave nature also ensures Araquanid moves as slow as possible, enabling it to outspeed as much as it can in Trick Room.
* An Adamant nature can be run instead if you want Araquanid to outspeed Alolan Marowak or Vikavolt outside of Trick Room. Along with the nature, 28 Speed EVs ensure Araquanid outspeeds Marowak, whereas 12 or more are sufficient for Vikavolt. This is useful for keeping them from harming your Trick Room setter too much.
* Water Bubble is the ability of choice due to its threefold benefits to Araquanid: it becomes immune to burns, resists Fire-type damage, and hits twice as hard with its Water-type moves.
* Waterium Z turns Liquidation into a 160-Base Power physical Hydro Vortex, and with Water Bubble and STAB still applied, even Pokemon that resist the move will receive a huge dent in their HP bar.
* Araquanid is bulkier than one might initially think. Do not be afraid to let it stay in and take a few hits if it means being able to dispose of a threatening foe.
* With Araquanid's low Speed stat, it is a good idea to put it on the team if you predict your opponent to be using a Trick Room playstyle. It may also be beneficial to bring it in against a team with Celesteela if you have few other means of dealing with it.
* Thanks to Water Bubble, there is little reason to use any offensive move other than Liquidation. Even on Pokemon that resist Water-type moves, it is usually stronger than Lunge.
* If Araquanid's Speed becomes problematic, do not be afraid of letting it slowly get KOed if it means stalling the opponent out to let a stronger threat come in for free later.
* Trick Room setters like Porygon2 and Oranguru are nigh on mandatory teammates to help Araquanid take advantage of its low Speed. If using Oranguru, Energy Ball might not be a bad tech choice to help deal with Gastrodon, and Porygon2's Toxic is also helpful.
* Kartana helps Araquanid take on bulky Water- and Electric-types, especially Gastrodon. In return, Araquanid can take out troublesome Fire-types.
* It is not a bad idea to have a Ground-type Pokemon like Garchomp into which Araquanid can switch to absorb an Electric- or Rock-type move.
* Politoed can help augment Liquidation's damage output with the weather it brings.
* Electric-type Pokemon like Tapu Koko and Xurkitree are helpful in taking out opposing Water- and Flying-types. They benefit from Araquanid's Wide Guard protecting them from Earthquake as well as its ability to switch into Tectonic Rage. If running Tapu Koko, be mindful that the Electric Terrain it brings will make it harder for Araquanid to tank opposing Electric-type attacks.
* On the other hand, you can run Alolan Marowak or Togedemaru to help redirect Electric-type moves with their Lightning Rod. Both are also useful in a Trick Room team, with the former being slow and strong and the latter helping set it up.
* Arcanine can help out against opposing Kartana with STAB Fire-type attacks and against opposing physical attackers in general with Intimidate.
* Poison Jab helps against Tapu Bulu and Tapu Fini, which resist Liquidation but are weak to Poison-type moves, along with anything that might be easier to handle if poisoned. Its power against other Pokemon is relatively weak, though, and Araquanid's STAB-boosted options are usually better.
* Leech Life lets Araquanid last longer on the field, but it usually does not heal significantly and Liquidation tends to be the better move to use anyway.
* Bug Bite lets Araquanid heal from foes' Sitrus and Figy Berries instead of them, but it is rather weak against everything else.
* Substitute with an Aguav Berry can turn Araquanid into a longer-lasting offensive threat. If no Trick Room is present, however, the Substitute is easy to remove and playing around the Berry from reduced HP is not difficult to do.
* If running another Water-type teammate, especially an offensive one, consider running Entrainment to give it Water Bubble.
* Soak changes the opposing Pokemon's type for easier KOs from Grass- and Electric-type teammates.
* Reflect helps the team take physical attacks better.
* If your team already has Z-Move users, Mystic Water is a viable replacement item to consistently make Liquidation a tad more powerful.
* Choice Band augments the power of each of Araquanid's moves, and it is almost always going to be using Liquidation anyway. This does, however, make Araquanid susceptible to exploitation by the opponent, as it cannot run utility moves.
* Wacan Berry is an option for making Tapu Koko's Electric Terrain-boosted Thunderbolt a guaranteed 2HKO, but it doesn't do much other than stop Electric-type attacks from dealing too much damage.
* Leftovers provides passive recovery, but again doesn't do too much else.
* A specially offensive set with Surf and Scald can be used, but it's overall a weaker option compared to a physically offensive one.
Checks and Counters
**Electric-types**: Tapu Koko, Alolan Raichu, Xurkitree, and Vikavolt naturally outspeed Araquanid and can deal considerable damage to it with their STAB moves, especially in Electric Terrain.
**Bulky Water-types**: Tapu Fini, Gastrodon, and Politoed must rely on coverage moves or rain-boosted STAB moves to deal any significant damage to Araquanid, but Araquanid cannot really hit them hard in return. Gastrodon is especially notable for locking Araquanid out of Liquidation with Storm Drain. Lapras is less common, but it is able to deal super effective damage with Freeze Dry. All of these Pokemon must watch out for Toxic or Poison Jab if Araquanid is running it.
**Kartana**: Thanks to its typing and naturally high Defense, Kartana is able to hit hard with its Leaf Blade, especially after a Beast Boost boost, and survive almost anything that Araquanid throws at it. It does not, however, appreciate any Lunges that would lower its Attack, as it would have to work a bit to regain the Attack.
**Intimidate**: Pokemon like Arcanine, Salamence, and Gyarados can reduce Araquanid's Attack with Intimidate, greatly limiting its damage output. The latter two also resist Liquidation and can retaliate with a strong or super effective STAB move.
**Slower Pokemon**: Pokemon like Snorlax and Gigalith that are naturally slower than Araquanid will conversely outspeed it in Trick Room and be able to deal considerable damage before it can do the same to them.