Feraligatr

It usually moves slowly, but it goes at blinding speed when it attacks and bites prey.

Ability — Torrential Heart: Once during your turn, you may put 5 damage counters on this Pokémon. If you do, during this turn, attacks used by this Pokémon do 120 more damage to your opponent's Active Pokémon (before applying Weakness and Resistance).

Giant Wave (160): During your next turn, this Pokémon can't use Giant Wave.