Jolteon ex (EX Delta Species 109/113)
Poké-POWER Evolutionary Thunder

Once during your turn, when you play Jolteon ex from your hand to evolve 1 of your Pokémon, you may put 1 damage counter on each of your opponent's Pokémon.

Lightning Colorless
Second Bite

Does 20 damage plus 10 more damage for each damage counter on the Defending Pokémon.

Lightning Colorless Colorless
Thunder Blast

Discard a Lightning Energy card attached to Jolteon ex.

Card rule

When Pokémon-ex has been Knocked Out, your opponent takes 2 Prize cards.