Generation Iii
Huge Power
Raises ATTACK.
Detailed Effect
This Pokémon's Attack is doubled while in battle. This bonus does not count as a stat modifier. This ability functions identically to Pure Power.
Pokémon With Huge Power
7 canonical Pokémon forms can have this Ability.

Marill 
Azumarill
Azurill
Mega Mawile
Mega Starmie
Bunnelby
Diggersby 