Moves

Giga Drain is a decent STAB option that 2HKOes Ground-, Water-, and Rock-types such as Mudbray, Chinchou, and Amaura while also providing Cottonee with passive recovery. Dazzling Gleam is a powerful Fairy-type STAB option that 2HKOes Dark- and Fighting-type Pokemon such as Vullaby, Timburr, and Mienfoo. Hidden Power Fighting can be used over either of Cottonee's STAB attacks to hit Pawniard for more damage and OHKO non-Eviolite variants, though Cottonee's STAB coverage is usually preferred, as it hits most of the tier neutrally. Encore receives priority from Prankster and is useful for locking foes into status moves as well as discouraging Pokemon such as Tirtouga and Croagunk from setting up on Cottonee. Memento can be used when Cottonee is weakened to severely lower a foe's offensive stats and allow a teammate to begin setting up more reliably. When used with Darkinium Z, Z-Memento will even fully heal an ally and nearly guarantee its setup. Knock Off is useful for removing items from foes and making them easier to whittle down if they were holding Eviolite. Tailwind receives priority from Prankster and can be used when Cottonee is weakened to give its teammates doubled Speed.

Set Details

Darkinium Z should only be used alongside Memento, as it grants Cottonee access to Z-Memento, which is helpful for supporting its teammates. 36 HP EVs, 40 EVs in each defensive stat, and an Eviolite provide Cottonee with reasonable bulk and allow it to avoid the OHKO from powerful hits in Abra's Psychic, unboosted Omanyte's Ice Beam, and Pawniard's Iron Head while allowing it to reliably switch into the likes of Carvanha and Choice Scarf Mienfoo. 140 EVs in Special Attack and maximum EVs in Speed with a Timid nature allow Cottonee to hit 17 Speed and outpace Scraggy and Pawniard as well as Speed tie with fast Mienfoo while hitting quite hard. Prankster is mandatory, as it gives all of Cottonee's status moves an important +1 boost in priority.

Usage Tips

It is of utmost importance that Cottonee's inability to hit Dark-type Pokemon with Prankster-boosted moves is noted, as it will fail to check Dark-type setup sweepers such as Scraggy and Vullaby. It is because of this that Encore and Z-Memento shouldn't be used on these foes to prevent generating free turns for the opponent. Cottonee's Prankster ability allows it to switch into resisted attacks and setup moves and lock foes into these moves with priority Encore. It is best for Cottonee to use Z-Memento when weakened, as this will allow it to safely bring in a teammate without wasting all of said teammate's HP immediately. Cottonee can also opt to use Z-Memento against threats that will likely OHKO it, such as Sludge Bomb Diglett and Gastly. If running Knock Off, Cottonee can use the move when predicting switches into Pokemon like Magnemite, Croagunk, and Ponyta in order to remove their items. Tailwind is best used when Cottonee is low on HP, as it allows Cottonee's teammates to receive a temporary 2x boost in Speed upon switching in after it has fainted. Cottonee must be wary of Poison-type coverage from foes, given its 4x weakness to the type. Diglett and Scraggy commonly carry Poison-type coverage and should have their potential coverage moves scouted out so Cottonee is able to properly check these threats. It is worth noting that Cottonee's attacks aren't capable of OHKOing most threats, which means that it will often require prior damage from either entry hazards or teammates to secure KOs on threats such as Pawniard and Vullaby. If Cottonee is running Z-Memento, the sweeper it is trying to support should feel free to set up and punch holes early-game, as it will likely be healed by Cottonee later on.

Team Options

Most Fire-types resist both of Cottonee's STAB attacks while OHKOing it with super effective STAB moves. As a result, reliable answers to Fire-types such as Shellder, Staryu, Onix, and Tirtouga all make for exceptional partners. Pokemon that are capable of switching into or removing Poison-type Pokemon and threats with Poison-type coverage such as Ferroseed, Mareanie, Abra, and Diglett, the latter of which in particular can use its Arena Trap ability to trap Poison-types, are all very appreciated by Cottonee. Pokemon that can take care of the many Flying-type Pokemon that threaten Cottonee, such as Amaura, Chinchou, and Magnemite, are also very appreciated. Powerful wallbreakers like Abra, Doduo, and Rufflet are capable of weakening or eliminating Cottonee's common checks in Ferroseed and Foongus and are also capable of muscling past bulkier threats to help Cottonee break through foes with more ease. Setup sweepers such as Tirtouga, Corphish, and Shellder all greatly appreciate the Memento support Cottonee is able to provide them with. Offensive Pokemon with rather average Speed such as Pawniard, Croagunk, and Snivy appreciate Cottonee's Tailwind support.