name: Substitute / Calm Mind
move 1: Substitute
move 2: Shadow Ball
move 3: Hidden Power Fighting
move 4: Calm Mind / Will-o-wisp
item: Salac Berry / Oran Berry
evs: 240 SpA / 240 Spe
Substitute and Salac Berry work together so well on Misdreavus. Switch him in on one of his 3 immunities, then Substitute on the switch. If the opponent is faster or ties, like Murkrow, Substitute to your Salac Berry and KO them. Otherwise, you could just attack the opponent.
Calm Mind is almost an afterthought on this set, but it's very important. If you predict a move like Sucker Punch or Stealth Rock, a free Calm Mind can be the difference between a sweep and just a KO or two. Secondly, it helps Misdreavus get a bit more bulk and become more likely to survive consecutive hits. If for some reason you don't see the need for Calm Mind, Will-o-wisp is there for Bronzor and Munchlax. Both become Substitute fodder with it.
Oran Berry is an option if you want to keep the Substitute game going longer.SET 2
name: Choice Specs
move 1: Shadow Ball
move 2: Hidden Power Fighting
move 3: Thunderbolt
move 4: Psychic
item: Choice Specs
nature: Modest / Timid
evs: 240 SAtk / 240 Spe
Just barely enough attacks to complete the set, but the coverage is nearly perfect. Hidden Power Fighting will 2HKO Munchlax even with the Oran Berry factored in, Shadow Ball gets STAB. Thunderbolt is a 100% accurate OHKO on stuff like Murkrow and Mantyke. Psychic is mainly for lack of a better move, but Misdreavus becomes a great counter to non-Sucker Punch Croagunk as well as Fighters in general with it.
Choice Scarf and Modest works, as it's always fun to hit everything with a Speed stat of 27.SET 3
move 1: Shadow Ball / Thunderbolt
move 2: Taunt
move 3: Will-o-wisp
move 4: Destiny Bond
item: Focus Sash / Colbur Berry
evs: 196 HP / 76 SpA / 236 Spe
Misdreavus has some awesome and uncommon moves in Taunt and Will-o-wisp that mess up leads like Bronzong and Murkrow. Combine that with its good Special Defense and Speed and you have a solid anti-lead Pokémon. Taunt messes up Stealth Rockers that ruin Focus Sashers. Will-o-wisp deals with Murkrow nicely as Misdreavus ties in Speed with Murkrow. This means that you'll burn a good 38% of the time if Murkrow has Taunt (50% chance of Taunting, 75% accuracy of WoW), assuming that you get no free turns from a mispredicted Sucker Punch. Destiny Bond is always a good move and should help Misdreavus take something out.
Misdreavus can run either Shadow Ball as a STAB attack or Thunderbolt specifically for Murkrow, which will OHKO. If you predict Sucker Punch, you should Burn Murkrow first.OTHER OPTIONS
Thunder Wave is a good status move, particularly on the Anti-Lead set. Will-o-wisp and Thunder Wave together can work with a double status set. Perish Song is a waste of time in Little Cup and Misdreavus has no Hypnosis to help with that. Other Hidden Power types are inferior to Fighting as coverage of Darks like Houndour is vital. As Misdreavus has more defense than most other Ghosts, a defensive set could work.EVs
With Hidden Power Fighting, you'll want 240 in the Base 85 stats to max them out, 236 without. If you don't run HP Fighting the remaining 36 EVs work in HP to add a point. The Anti-Lead has maximized HP instead of Special Attack to take hits slightly better.. OPINION
One of the better Pokémon that went off and evolved, Misdreavus is an amazing Little Cup sweeper. With STAB Shadow Ball off of 85 Special Attack and Speed, Misdreavus hits very hard and even beats Munchlax with Will-o-wisp. It's even faster than Gastly too! Misdreavus also has decent defenses and extremely important immunities, making her an all around useful Pokémon for any team.COUNTERS
As with everything in Little Cup, an exact counter is hard to come by. Barring Will-o-wisp or predicted Choice Specs Hidden Power Fighting, Munchlax can beat Misdreavus with his Ghost immunity and access to Pursuit.
Close behind Munchlax are other Ghost resists, with appropriate prediction or secondary typing. Without Thunderbolt, Taillow and Starly are decent, while Murkrow is of course the ideal switch-in to any set without Will-o-Wisp or Thunderbolt
As for revenge killers and other sketchy counters, Pursuiters like Buizel and Larvitar can come in on a non-SE move, especially Calm Mind, and KO. Gastly is faster than Misdreavus if Gastly holds a Choice Scarf.