Moves
U-turn allows Primal Kyogre to pivot which allows it to gain momentum and health through Regenerator, and unlike Volt Switch and Parting Shot, it cannot be blocked. Revelation Dance is a decently powerful STAB move that hits Normalize Mega Gengar, as it ignores Normalize when Primal Kyogre gets hit with Entrainment, and can chip opposing Pokemon such as Registeel and Mega Audino. If Mega Gengar is not a problem, Scald can be run to spread burns, and it is also useful to wear opposing Pokemon down and deter Sturdy Shedinja. However, Primal Kyogre becomes more difficult to Imposter-proof because of the threat of burns, most likely requiring a Pokemon with an ability like Comatose or Poison Heal, limiting the team options. Spectral Thief lets Primal Kyogre steal stat boosts from the opposing Pokemon, letting it reliably check threats like Poison Heal Primal Kyogre and Xerneas while preventing Kyogre from being setup fodder. Core Enforcer can nullify useful abilities like Poison Heal and Regenerator and hits Dragon-types like Giratina and Mega Garchomp hard. Nuzzle is an option to be able to slow down fast sweepers and help with non-Choice Scarf Imposter Speed ties. However, Imposter users will be able to paralyze your Pokemon as well, limiting the possible Imposter-proofs for Primal Kyogre to status-immune Pokemon such as Comatose Giratina. Ice Beam provides decent coverage with Revelation Dance or Scald and OHKOes Mega Garchomp, which can usually force Primal Kyogre out. If the team lacks an entry hazard remover, Rapid Spin can be run. However, this is a poor move on Primal Kyogre, as it fails to pressure common spinblockers like Giratina. Rapid Spin should be run along with Scald to effectively annoy Giratina with Scald burns and Core Enforcer nullifying Poison Heal, while also forcing out Shedinja, another spinblocker.
Set Details
A Sassy nature along with 0 Speed IVs is run to maximize Primal Kyogre's special bulk while letting it Speed tie with opposing mininum investment base 90 Speed Pokemon to slow pivot, letting it bring in frail teammates in safely. As an alternative, 116 Speed EVs and a Sassy nature let Primal Kyogre outspeed everything up to and including base 150 Speed Pokemon after stealing a Shell Smash boost, allowing it to KO the opposing Pokemon before taking another hit. This comes at a cost of almost always outspeeding opposing defensive pivots, however. An Assault Vest further amplifies Primal Kyogre's special bulk, letting it take on powerful special attackers like Mega Mewtwo Y and Mega Gengar better. Regenerator allows Primal Kyogre to regain a third of its health every time it switches out, and is the only way for this set to recover health. This differentiates from other healing methods, as it doesn't force Primal Kyogre to lose momentum by using a recovering move.
Usage Tips
Switch Primal Kyogre in against special attackers it can handle, such as Mega Gengar, opposing Primal Kyogre, and Xerneas. It is important to scout the moveset of the Pokemon you are planning to switch Primal Kyogre into, as it may carry a strong coverage move, such as Bolt Strike on Sheer Force Mega Mewtwo Y. Be careful with strong physical attackers, as Primal Kyogre's modest physical bulk isn't enough to take strong hits. Since this set does not carry Safety Goggles, beware of Spore, as it cripples Primal Kyogre. Since Primal Kyogre needs its Assault Vest to check the special attackers it is supposed to check, avoid Knock Off, as it will reduce Primal Kyogre's special bulk. If Primal Kyogre is low on HP, switch it in safely and switch out to instantly to regain a third of its health. Because Primal Kyogre is reliant on Regenerator as its only form of recovery, avoid Core Enforcers from slower Pokemon like Registeel and Mega Audino. U-turn is excellent for regaining health with momentum, chipping opposing Pokemon and bringing in teammates safely, and is very easy to spam, especially if the opposing Pokemon is unable to pressure Primal Kyogre. Revelation Dance and Scald are also easy to spam thanks to STAB, being able to chip opposing walls and, in Scald's case, spread burns. If the opposing Pokemon is a setup sweeper, Spectral Thief will steal the stat boosts and neuter their power. While this set is vulnerable to Imposter users, using Scald or Nuzzle can burn or paralyze them, reducing their effectiveness.
Team Options
Steel-types such as Registeel and Celesteela are appreciated in taking on -ate Pokemon like Mega Diancie and Kyurem-B which can target Primal Kyogre's poor physical bulk. They also can take on strong physical attackers like Kartana that threaten Primal Kyogre. Imposter Chansey is useful for scouting oposing movesets, which help determine if Primal Kyogre can switch in against opposing attackers. Entry hazard removers like Magic Bounce Giratina and Mega Audino are appreciated, as Primal Kyogre hates taking chip damage, even with Regenerator. A Knock Off absorber like Griseous Orb Giratina or a Poison Heal user with its Toxic Orb already activated prevents Primal Kyogre from losing its very important Assault Vest. Dragon-types like Giratina and Zygarde-C can tank the Grass- and Electric- type moves targeted at Primal Kyogre and also help with answering Red Orb Groudon. Physical walls like Mega Slowbro and Prankster Giratina check dangerous physical wallbreakers, which force Primal Kyogre out. It is necessary to have a Pokemon that can take care of an opposing Imposter user that transformed into Primal Kyogre, as this set often gives free recovery for the opponent's Imposter. Examples include Red Orb Groudon, Ferrothorn, and Comatose Giratina. In addition, Toxic Spikes, offensive Poison Heal users like Regigigas and Xerneas, and Mold Breaker attackers such as Mega Gengar that can pressure opposing Imposter users are appreciated. Primal Kyogre's longevity and bulk allow it to be paired with powerful special attackers that it can Imposter-proof, such as Kyurem-W.