Meowscarada @ Expert Belt
Ability: Protean
Tera Type: Flying
EVs: 252 Atk / 4 SpD / 252 Spe
Jolly Nature
IVs: 0 SpA
- Flower Trick
- Night Slash
- U-turn
- Aerial Ace
Flower Trick: Probably self-explanatory, but it's a STAB move that always critical hits, and never misses
Night Slash: I chose Night Slash over Knock Off because as another answer mentioned, Knock Off is only effective 6 times at best (And Night Slash also has a high critical hit ratio and STAB)
U-turn: To escape unfavorable matchups, while dealing damage. This is also super effective on Psychic types
Aerial Ace: To deal with bug and fighting types, which deal 4x and 2x damage respectively. I gave Meowscarada the Tera flying type for this reason, but this may be risky as it introduces a 4x weakness to the ice type
The Protean ability for STAB on each move, Expert Belt to increase effectiveness of super effective hits, and Jolly nature to increase its already comical speed