So Ghost you can't even see the purple
* Arceus-Ghost's typing leaves few Pokemon resistant or immune to its STAB moves, and it can make a big dent to them thanks to the high power of its main STAB move.
* Extreme Killer's popularity and the nature of Team Preview make Arceus-Ghost harder to plan for before it is actually sent out.
* Solid defensive stats and typing allow it to have a favorable offensive matchup against its Normal-type forme, act as an effective spinblocker, and possibly withstand strong hits from the likes of Deoxys-A and boosted Mega Salamence.
* Multitype's updated mechanics give it access to a powerful, single-use nuclear weapon that can obliterate virtually anything after a Swords Dance boost.
* Arceus-Ghost does not appreciate the popularity of Yveltal, Choice Scarf Lunala, and Mega Gengar on teams, all of which can effectively deal with it.
* Its coverage moves are rather weak without anything apart from Swords Dance to increase their power, meaning its damage output will be quite low if it has to resort to these moves.
* Given its limited options, it is rather one-dimensional, and it is not difficult to predict what it'll try to do.
* As Never-Ending Nightmare only has one use, Arceus-Ghost has few means of taking opposing bulky Pokemon afterwards, which can successfully set up what they need to in the meantime or deal strong damage in retaliation.
name: Swords Dance
move 1: Swords Dance
move 2: Shadow Force
move 3: Brick Break
move 4: Extreme Speed / Shadow Claw / Recover
item: Ghostium Z / Spooky Plate
evs: 252 Atk / 4 Def / 252 Spe
* Swords Dance augments its power to incredible levels, after which its attacks do considerable damage to most of the tier.
* Shadow Force is an incredibly strong Ghost-type move, capable of putting in great damage against anything that doesn't resist it after an Attack boost.
* Brick Break is not a very strong move on its own, but it's the only Fighting-type move Arceus-Ghost gets, and Ghost- and Fighting-type coverage is not resisted by any single Pokemon in the game. The ability to break the occasional Light Screen and Reflect can also come in handy, and the Extreme Killer matchup is rather favorable with the coverage it provides.
* Extreme Speed is a strong priority attack that can swiftly pick off weakened threats that would otherwise outspeed Arceus-Ghost.
* Shadow Claw can be used as a (backup) single-turn attack to take out immediate threats like Ghost-types before they have a chance to switch out.
* Recover can also be used for active healing to prolong Arceus-Ghost's longevity.
* Maximum investment in Attack and Speed ensures Arceus-Ghost hits as hard as possible and, with a Jolly nature, moves as soon as possible. This allows it to at the very least Speed tie with opposing Arceus.
* Ghostium Z turns Shadow Force into Never-Ending Nightmare, which deals incredible damage to even resisted threats. After a Swords Dance, offensive Yveltal variants faint outright after Stealth Rock.
* Spooky Plate can be used instead to give a continuous power boost to all of its Ghost-type moves rather than a one-time nuke.
* Arceus-Ghost can deal immense damage to the opposing team, so it should be saved for mid-game or late-game sweeps when Pokemon that can tank its hits are weakened. However, if you have other dedicated sweepers in the back, feel free to send it out early to start applying immediate pressure.
* Do not be hasty in using Never-Ending Nightmare. Arceus-Ghost only gets one chance at nuking something, so make sure it is a threat worth nuking, such as Primal Groudon, support Arceus, Mega Salamence, or weakened Yveltal. If you see a Normal-type Pokemon on the opponent's side, unless you know for sure it isn't Arceus-Normal, hold off on the Z-Move.
* Keep Arceus-Ghost's HP as high as possible. As the set name implies, Arceus-Ghost should be used less to tank hits from the opposing team and more to deal heavy damage to it. It appreciates all the field time it can get, and full HP ensures it can survive Gengar's Shadow Ball or Choice Scarf Lunala's Moongeist Beam and retaliate with a super effective move.
* Shadow Force only has 8 PP, one of which is consumed by its Z-Move if running Ghostium Z. Be mindful of that before you start spamming it.
* Entry hazards, particularly Stealth Rock, can help Arceus-Ghost by putting more opposing Pokemon into KO range of its Z-Move. Notable hazard setters include Primal Groudon, Dialga, and Cloyster, all of which appreciate its ability to block foes from spinning their hazards away.
* Primal Groudon in particular synergizes well with Arceus-Ghost, absorbing Will-O-Wisps and Thunder Waves aimed at the latter, tanking strong physical hits with its high Defense, and weakening the opponent's team with its strong hits in retaliation.
* Xerneas appreciates this Pokemon's ability to check Steel-types like Magearna, Solgaleo, and Aegislash, and in return it helps out against the Dark-types that pester it.
* Cloyster and Excadrill help keep Arceus-Ghost safe from entry hazards with Rapid Spin. Defog users are also appreciated, but there are few, if any, Ubers-viable Defog users that do not violate Species Clause or share a weakness to common offensive typings.
* Other strong sweepers, like Deoxys-A and Mega Salamence, appreciate the damage that Arceus-Ghost deals to the opposing team, and they can also apply pressure of their own for it to come in and finish the job later. Deoxys-A enjoys Arceus-Ghost's immunity to Extreme Speed that would easily take it out, and Salamence can Intimidate physical attackers before it Mega Evolves or help wear down physically defensive Pokemon.
* Arceus-Ghost appreciates help from a strong foundation that can take on Xerneas. It cannot easily take on Xerneas on its own, even with Primal Groudon in the back, so other means of dealing with it like Mega Lucario, priority attackers, Roar on Primal Groudon, or even entry hazard stackers are appreciated.
* Chople Berry Tyranitar deserves a mention for its ability to effectively wall Yveltal and Pursuit trap fast Ghost-types.
* Arceus-Ghost can run a Calm Mind or support set that makes use of its Special Attack or bulk, respectively, but it usually finds itself outclassed in these roles by other Arceus formes.
* Stone Edge can help it reliably take on Yveltal, but it loses out on some important coverage with Brick Break, and a boosted Never-Ending Nightmare is usually sufficient.
Checks and Counters
**Arceus-Dark**: Arceus-Dark can OHKO Arceus-Ghost with Judgment coming off only a single Calm Mind, while the latter needs two Brick Breaks at the minimum to KO the former. If the latter has less than 67% HP remaining, the former can even forgo the Calm Mind and take the KO right away.
**Yveltal**: While offensive variants cannot take a +2 Never-Ending Nightmare if they have taken Stealth Rock damage, Yveltal can easily take all of its other moves and KO in return with a strong Dark-type attack. Physically defensive variants, while rare, can take the boosted Z-Move.
**Other Dark-types**: Chople Berry Tyranitar can take a +2 Brick Break and OHKO with Foul Play in return. Darkrai can outspeed Arceus-Ghost and either try to put it to sleep and set up or deal heavy damage with Dark Pulse.
**Fast Ghost-types**: Ghost-types that can outspeed Arceus-Ghost, such as Mega Gengar and Choice Scarf Lunala, are immune to its coverage moves and can deal heavy damage to it in return. If it has taken some chip damage already in the case of the former, or simply Stealth Rock damage in the case of the latter, that heavy damage will become an OHKO.
**Normal- and Ghost-type Combination**: Continuous, well-timed switching between a Ghost-type and a Normal-type is an effective means of stalling out Arceus-Ghost's PP. Entry hazards do diminish the effectiveness of this strategy, and a Shadow Claw or a Never-Ending Nightmare on the Ghost-type will cut this method short.
**Zygarde-C**: A Zygarde-C at full HP can survive a +2 Never-Ending Nightmare and Rest off the damage afterward, causing Arceus-Ghost to waste its Z-Move, but it usually tends to be asleep at full HP. It can also Dragon Tail the latter's boosts away, or it can apply a status condition to hinder its sweep.
**Status Conditions**: Support Arceus formes can take any hit other than a boosted Z-Move and use Will-O-Wisp or Toxic in return. Pokemon with Prankster, like Klefki and non-Mega Sableye, can apply statuses of their own before Arceus-Ghost makes any move. Hex Mega Gengar naturally outspeeds Arceus-Ghost and can burn it before it uses its Ghost-type move. All of these status conditions hinder Arceus-Ghost's sweep in some way, either making it physically weaker, slowing it down, or greatly reducing its field time.
**Mega Salamence**: Bulky Mega Salamence variants can take an unboosted Shadow Force with ease, set up a Dragon Dance, and have a chance of KOing back hard with a strong Double-Edge. It should be noted that if Arceus-Ghost is already set up, a Shadow Force will deal enough damage to KO after Stealth Rock damage or a follow-up Extreme Speed.