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Gyarados-Mega (M) @ Gyaradosite
Ability: Mold Breaker
EVs: 252 Atk / 4 SpD / 252 Spe
Adamant Nature
- Crunch
- Dragon Dance
- Aqua Tail
- Avalanche
You dragon dance then mega evolve to mold breaker through the disguise with a crunch for a one hit KO.