Swalot @ Poisonium Z
Ability: Liquid Ooze
EVs: 252 Atk / 4 SpD / 252 Spe
- Gunk Shot
- Ice Punch
- Gastro Acid
Gunk Shot is for a high base power STAB move. Earthquake allows Swalot to hurt Steel types. Ice Punch is to hit Ground types hard. Gastro Acid is used for two reasons: One is to shut down some Pokemon that rely on their abilities. Another is to boost Speed with Z-Gastro Acid, increasing Swalot’s sweeping capabilities.
The EVs on this set gives Swalot the ability to sweep. Liquid Ooze punishes Pokemon like Mega Venusaur. Poisonium Z allows Swalot to utilize Z-Gastro Acid. Finally, a Timid nature makes Swalot as fast as possible, alongside the speed boost from Z-Gastro Acid.
Hope this set answers your question!