The Creator lurks in the shadows with the attachment of the Dread Plate, and lies in wait for prey to come by for Him to pounce on. The Master of the night's opaque Judgment crushes His abundant Psychic- and Ghost-type children that reside in the Uber tier. While the deity of terror is Himself scared witless by Bugs and Fighters, and cannot hope to scratch the hide of Steel-clad Pokemon, the former two are rare in Ubers, and the latter are eradicated by a swift Focus Blast. The tenebrous One is also seemingly outclassed by its ectoplasmic counterpart, Ghost Arceus; however, nothing is immune to Dark Arceus's piercing Judgment. Cower in fear before the Master of horrors!
In a tier infested with Psychic-type Pokemon, Dark Arceus makes an excellent Calm Mind mono-attacker, as nothing is immune to its STAB Judgment, a move with solid coverage overall. With Calm Mind boosting its already stellar special stats, Refresh eliminating bothersome status, and Recover healing any damage it has sustained, Dark Arceus can be incredibly difficult to take down, especially for stall teams.
Not only do Dark-type Judgments hit many Ubers super effectively, but very few Pokemon commonly found in the tier resist the attack. Thanks to its great coverage, Dark Arceus can afford to eschew a secondary attack for a useful support move to help it set up. More often than not, this move should be Refresh, as it prevents Dark Arceus from being crippled by status. The Achilles' heel of most Calm Minders is status, specifically Toxic damage, and so Dark Arceus's ability to cleanse itself with Refresh greatly separates it from other Calm Mind sweepers. As previously mentioned, this specific Arceus excels at breaking stall teams. With Refresh removing poison from Toxic Spikes and Recover to heal residual damage, stall teams will struggle to defeat Dark Arceus. In addition, common stall team phazers such as Lugia and Groudon can't keep absorbing boosted Judgments. While Refresh gives Dark Arceus near-unparalleled stallbreaking abilities, there are a few other feasible options, each with their pros and cons. If one feels an auxiliary attacking move is necessary, Focus Blast is the ideal choice for nearly perfect neutral coverage alongside Judgment, although Dark Arceus will have a much harder time breaking stall and staying alive in general. However, Focus Blast allows Dark Arceus to deal with its most common counters, including Tyranitar, Lucario, and Scizor. On the other hand, Substitute can block incoming status moves while also allowing Dark Arceus to scout switch-ins, but it's generally inferior to Refresh because it leaves Dark Arceus helpless against Toxic Spikes.Team Options & Additional Comments >>>
Other than Focus Blast and Substitute, there are very few other options for Dark Arceus to use. Flamethrower deserves mention as a secondary attack to roast any Scizor or Heracross bold enough to switch in, but it has fairly poor coverage, and it still leaves Dark Arceus walled by Heatran and Tyranitar. An entirely offensive Calm Mind set with Judgment / Focus Blast / Ice Beam hits the majority of Uber Pokemon super effectively, although it struggles with stall and does not make use of the excellent bulk Dark Arceus possesses. Any Swords Dance Dark Arceus set is discouraged due to the lack of a reliable physical STAB move; it is completely outclassed by its Ghost counterpart.
Checks and Counters
Dark Arceus is extremely difficult to take down because its weaknesses are uncommon in Ubers, coupled with the fact that Refresh and Recover greatly increase its longevity. Even Pokemon who resist Judgment like Forretress will struggle to do any meaningful damage back to Dark Arceus; its most solid counters will resist Dark and threaten it back with powerful attacks.
Scizor and Lucario are among Dark Arceus's top counters, thanks to their resistance to Dark and their super effective STAB attacks. Although rare, Heracross resists Judgment and its dual STAB is super effective against Dark Arceus. Infernape also resists Judgment, and can threaten with Close Combat or U-turn. Tyranitar has excellent Special Defense and resists Judgment, although its lack of super effective attacks to damage Dark Arceus can cause it to become set-up fodder unless it packs Dragon Dance. Dark Arceus's Bug and Fighting counterparts deserve mention since they have super effective STABs, and the latter resists Dark Arceus's Judgment. Heatran's Taunt can prevent Dark Arceus from healing or boosting, and it can use powerful Fire Blasts to scare Dark Arceus away. Although most Dialga will have difficulties hurting Dark Arceus after a few Calm Minds, mixed variants can threaten with Brick Break and Bulk Up versions can boost alongside it. With their excellent Special Defense and powerful attacks, Ho-Oh and Calm Mind Kyogre will almost always defeat Dark Arceus in a one-on-one situation.
Without Refresh, Dark Arceus's great coverage will make it hard to switch into, although it will be quickly worn down by status and is vulnerable to stall. If Dark Arceus chooses to use Focus Blast, Blissey's unmatched defenses will let it absorb any attack and get a Toxic off to effectively cripple Dark Arceus. By extension, any Dark Arceus lacking Refresh is extremely susceptible to Toxic Spikes.