If Sharpedo is your Active Pokémon and is damaged by an opponent's attack (even if Sharpedo is Knocked Out), flip a coin. If heads, discard an Energy card attached to the Attacking Pokémon.

Crunch20

If an attack does damage to the Defending Pokémon (after applying Weakness and Resistance), that attack does 40 more damage to that Pokémon until the end of your next turn.