Psyduck

It has mystical powers but doesn’t recall that it has used them. That is why it always looks puzzled.

Tripping Headbutt: Flip a coin. If heads, this attack does 30 damage to 1 of your opponent's Pokémon. If tails, this attack does 30 damage to 1 of your Pokémon. (Don't apply Weakness and Resistance for Benched Pokémon.)