Paralysis is slightly less of a devil
Mismagius is a fast and strong Ghost-type attacker with access to Nasty Plot, allowing it to outspeed most cores and break them down with boosted attacks that are hard to resist. Mismagius benefits massively from Z-Moves, which give it the destructive power to compensate for the average Base Power of its attacks and capitalizes on its expansive offensive movepool, making it difficult to defend against. It is the fastest spinblocker in the tier, which can be a useful asset for offensive teams. However, Mismagius suffers from awkward bulk that does not complement its typing, as its physical Defense is too low to effectively make use of its resistances and immunities. This means that Mismagius is usually forced to set up Nasty Plot against Choice-locked Normal-, Fighting-, and Ground-type attacks, or against uninvested attackers such as Garbodor, Weezing, Slowbro, and Vileplume, usually taking some substantial damage in the process.
name: Nasty Plot + 2 Attacks
move 1: Nasty Plot
move 2: Shadow Ball / Hex
move 3: Dazzling Gleam
move 4: Taunt / Will-O-Wisp
item: Ghostium Z / Colbur Berry
evs: 252 SpA / 4 SpD / 252 Spe
Nasty Plot doubles Mismagius's Special Attack, making its Ghost-type attacks significantly more dangerous. Shadow Ball is Mismagius's most consistent STAB move. However, Hex can reach insane levels of damage output against targets which have been afflicted with a status condition, though this means that Hex should not be used without Will-O-Wisp. It should be noted that both moves reach 160 Base Power when used as a Z-Move, despite their difference in Base Power. Dazzling Gleam is Mismagius's most consistent coverage move, smacking bulkier Dark-types such as Scrafty and Guzzlord for massive damage while hitting the Normal-types and other Dark-types in the tier for at least neutral damage. Taunt can be used to break stall, preventing recovery and status from bulkier walls that otherwise can't hurt Mismagius too much. It can also be used to prevent setup such as Shell Smash or Trick Room, preventing the opponent from getting an offensive edge over Mismagius. Will-O-Wisp is used to maximize Hex's damage potential, as well as crippling physical attackers, particularly Drapion and Braviary, and might allow Mismagius to survive an otherwise fatal hit. It is especially effective when used alongside Colbur Berry, allowing Mismagius to survive Pursuit encounters from slower Pokemon and even potentially beat them one-on-one.
Maximum Special Attack and Speed investment makes the most out of Mismagius's offensive capabilities. Mismagius's Speed tier mandates a Timid nature, allowing it to outrun important threats such as Delphox, Sigilyph, Drapion, and Houndoom, as well as Speed tie with Scyther and offensive Cryogonal. Mismagius's item serves to temporarily enhance its strength or its bulk, and weaken Knock Off's damage output. Ghostium Z gives Mismagius access to a 160 Base Power Ghost-type nuke. Colbur Berry is a more conservative option to give Mismagius better survivability against Drapion's Knock Off, Houndoom's Dark Pulse, and various Pursuit and Sucker Punch users, which can allow Mismagius to escape from or break through them. It is a fine alternative for an item if the team already has a Z-Move user.
When using Mismagius, one should identify the opponent's offensively weakest link, set up on that, and try to break and disrupt the opponent's team from there. Usually the most frequent and best setup fodder for Mismagius comes in the form of the opponent's bulky Poison-type, such as Garbodor, Qwilfish, Weezing, or Vileplume, as they do not threaten Mismagius much in terms of damage. However, Mismagius wants to be cautious around Qwilfish and Vileplume due to their ability to induce paralysis or sleep, so it is usually better to Taunt them before setting up. Mismagius may also use its immunities to take advantage of any Choice-locked Pokemon using Normal-, Fighting-, and Ground-type moves.
Alternatively, Mismagius can find setup opportunities by threatening the opponent's slower Psychic- and Ghost-types, such as Delphox, Sigilyph, Xatu, Jellicent, and Slowbro, and set up Nasty Plot that way. Be warned that Mismagius's unboosted Shadow Ball isn't strong enough to OHKO the bulkier Ghost- and Psychic-types, which can lead to painful retaliation. Once set up, Mismagius can start breaking through with its powerful neutral Ghost attacks. Ghostium Z Mismagius shouldn't be afraid to unleash the Never-Ending Nightmare if it can KO something that Shadow Ball would not, as Mismagius would be unlikely to find another opportunity to threaten KOs like this afterward. Colbur Berry Mismagius can afford to take it at a slower pace, using Will-O-Wisp to soften up foes and cripple their offensive capabilities before using boosted Hex to finish them off.
Offensive Dark-types such as Sneasel, Drapion, Absol, and Scrafty pair well with Mismagius; both of them can put substantial offensive pressure on the opponent and overwhelm their defenses, particularly with the Dark-types disposing of Meloetta, especially with Pursuit. The Dark-types also provide defensive synergy between each other, as Dark-types resist both of Mismagius's weaknesses while Mismagius can switch in on Bug-, Fighting-, and Ground-type moves aimed at them. Fighting-types such as Hitmonlee, Emboar, Machamp, Virizion, and Toxicroak work really well offensively with Mismagius, being able to break down and soften up the opponent's team for each other. Not only do they resist Dark-type moves for Mismagius, but they also bait out bulky Poison- and Psychic-types such as Qwilfish, Slowbro, Weezing, and Xatu, which Mismagius loves to prey on.
Entry hazards certainly makes Mismagius's job of breaking cores a lot easier: Stealth Rock can weaken some of Mismagius's answers, such as Houndoom, Braviary, and Incineroar; Spikes help by further inching foes into KO range, which can allow Mismagius to hold onto its Never-Ending Nightmare; and Toxic Spikes easily fuels Mismagius's Hex. Furthermore, Mismagius's Ghost typing and access to Taunt can allow it to prevent both Rapid Spin and Defog as well as threaten Xatu, making pretty much any entry hazard user complement Mismagius effectively. Among the most notable ones would be Steelix, Seismitoad, Rhydon, Garbodor, Qwilfish, Piloswine, Ferroseed, and Omastar. Shuckle is especially notable as a teammate, as Taunt Mismagius can help preserve Sticky Web quite well.
name: Rockium Z
move 1: Nasty Plot
move 2: Shadow Ball
move 3: Power Gem
move 4: Dazzling Gleam
item: Rockium Z
evs: 252 SpA / 4 SpD / 252 Spe
Nasty Plot doubles Mismagius's Special Attack, giving Mismagius much greater breaking power. Shadow Ball is Mismagius's STAB move and most consistent source of damage output, due to its strong neutral coverage. Power Gem, when boosted by Rockium Z, turns into Continental Crush, which nabs incredible KOs on many of Mismagius's answers. +2 Continental Crush OHKOes Assault Vest Incineroar, Substitute + Bulk Up Braviary, Drapion, and Skuntank, whereas a +0 Continental Crush can OHKO Houndoom and offensive Braviary with more surprise factor than a +2 Power Gem. Power Gem is also capable of taking down Charizard and offensive Scyther, though Mismagius risks a Speed tie with the latter. Dazzling Gleam rounds off Mismaagius's coverage by nabbing Scrafty, which otherwise resists both of its attacks, as well as nailing Guzzlord and checking Fighting-types slightly more effectively.
Maximum Special Attack and Speed investment maximizes Mismagius's offensive presence. A Timid nature is mandatory, as Mismagius has an important Speed tier, being able to Speed tie with Scyther and Cryogonal while outrunning the likes of Delphox and Sigilyph. It is especially important for this set to outspeed Houndoom and Drapion, given the set's intention to bait them into an unexpected KO. Rockium Z is the obvious item of choice, as it covers the most out of Mismagius's checks.
Mismagius should set up Nasty Plot by either taking advantage of the opponent's more passive Pokemon, particularly bulky Poison-types, setting up safely against Choice-locked Normal-, Fighting-, and Ground-type moves, or threatening out slower Ghost- and Psychic-types with its Shadow Ball. This variant of Mismagius is much more geared towards handling its checks, essentially acting as a lure, but it still has considerable power at breaking cores in general. It also should be noted that +2 Continental Crush guarantees the OHKO on all but the very bulkiest of Cryogonal, which can be a valued asset for certain teams that are vulnerable to it.
Given this Mismagius's ease at disposing of its potential answers, setup sweepers that appreciate the removal of these Pokemon make for the best partners. Lilligant in particular benefits massively as it shares many of its checks with Mismagius, meaning Rockium Z Mismagius is very effective at clearing the way for Lilligant to sweep with Quiver Dance. Specially offensive Sceptile is a notable beneficiary as well, as it detests bulky Braviary and can help attract bulky Poison-types for Mismagius to set up on. Offensive Psychic-types such as Meloetta, Sigilyph, and Delphox also like having the opponent's bulkier Dark-types out of the picture, giving them more room to wreak havoc. This Mismagius set can fall prey to Sneasel and Choice Scarf Drapion, and its partners can be just as vulnerable, thus having a backup response against those attackers is of utmost importance. Bulky Pokemon that can punish or just take Knock Offs are good partners, such as Rocky Helmet Garbodor, Steelix, Qwilfish, Hitmontop, Granbull, and Alolan Persian, which can offer their respective support via entry hazards, spinning, Heal Bell, status, or pivoting. More offensive responses, such as Emboar, Scrafty, and Incineroar, can punish with insane damage, setup, or pivoting with U-turn.
Mismagius's movepool is quite large for a Ghost-type, though it has minimal use for the majority of them. Its offensive movepool contains moves such as Dark Pulse, Energy Ball, Mystical Fire, and Thunderbolt. Among those listed here, Darkinium Z Dark Pulse has the most appeal for its ability to wipe out Meloetta after a Nasty Plot, but it targets only a single Pokemon and heavily overlaps coverage with Mismagius's Ghost STAB, which makes it not worth the use of a Z-Move, and you'd be far better off just Pursuit trapping Meloetta. Mismagius's Speed allows it to make mild use of Memento and Destiny Bond, with the former setting up a sweep for a teammate while the latter potentially forcing an unexpected double KO. Mismagius has access to other status moves such as Pain Split, Heal Bell, Mean Look, and Perish Song, but its awkward bulk and typing drastically decrease the usefulness and consistency of these moves on utility sets.
Checks and Counters
**Pursuit**: Mismagius's poor physical bulk and Dark weakness leave it vulnerable to Pursuit. Faster Dark-type Pursuit users such as Sneasel and Choice Scarf Drapion exert immense pressure on Mismagius, as they can also threaten an immediate KO with Knock Off on non-Colbur Berry variants, leaving Mismagius in trouble whether it switches out or not. Slower Pursuit users such as Absol, Skuntank, and Spiritomb can prompt Mismagius to flee by threatening a KO with Sucker Punch which can set up for a KO with Pursuit instead, but Colbur Berry + Will-O-Wisp Mismagius might be able to turn the tables. More unexpected Pursuit users, such as Dodrio and Tauros, are also successful at trapping Mismagius, so long as they present enough of a threat to force it out in the first place.
**Normal-types**: Meloetta is Mismagius's hardest defensive counter, with its large special bulk and neutrality to nearly all of Mismagius's attacks allowing to take +2 hits with ease and doing major damage back with Psychic STAB moves or Shadow Ball. Substitute + Bulk Up Braviary soaks up Mismagius's neutral attacks and Roosts off the damage, but it must be wary of +2 Continental Crush, which OHKOes it. Dodrio, Choice Scarf Braviary, Cinccino, Ambipom, and Tauros can switch in on Shadow Ball and offensively check Mismagius, although Flying-types don't want to switch into Rock-type moves while Tauros does not have a way to OHKO a healthy Mismagius. Specially defensive Normal-types with Knock Off, namely Audino and Lickilicky, can prove to be annoyances as well, especially when Audino has Regenerator to heal off excessive damage while Lickilicky's Oblivious blocks Taunt.
**Dark-types**: Sneasel is Mismagius's greatest nemesis, as it outspeeds and has a high chance to OHKO Mismagius even through Colbur Berry with its Life Orb-boosted Knock Off, and it can use that threat to play further mind games with Pursuit. Alolan Persian also outspeeds Mismagius and can check it in a pinch with Black Hole Eclipse, though Foul Play's inability to OHKO Mismagius means it risks losing to +2 Dazzling Gleam. Assault Vest Incineroar easily keeps Ghostium Z and Colbur Berry Mismagius in check, but it has to watch out for Continental Crush variants. Sucker Punch users such as Absol, Spiritomb, Skuntank, and Houndoom can keep Z-Move Mismagius in check, although the former three need to be wary of Colbur Berry + Will-O-Wisp variants. If Mismagius has expended its item in any way, Houndoom and non-Choice Scarf Drapion become serviceable checks, especially if they bait out the Z-Move and sacrifice a teammate to waste it.
**Faster Physical Attacks**: Nearly any physical Choice Scarf user presents a substantial threat to Mismagius, with Pokemon such as Emboar, Hitmonlee, Drapion, and Medicham threatening an outright KO, if not massive damage at the least. The likes of Swords Dance Virizion and Psyshock Alolan Raichu can also pick off a weakened Mismagius. Mismagius's poor Defense also leaves it quite vulnerable to priority moves, particularly Sucker Punch from the likes of Toxicroak, Emboar, Hitmonlee, and Kangaskhan, though Colbur Berry can slightly alleviate this weakness. However, other priority moves such as Aqua Jet and Ice Shard can still do a number, and Mismagius especially does not appreciate Scrappy Fake Out from Kangaskhan or Shadow Sneak from Spiritomb.