Neo-Spacian Aqua Dolphin (DP03-EN005) - Duelist Pack 3: Jaden Yuki 2 Unlimited

Once per turn, by discarding 1 card, look at your opponent''s hand and select 1 Monster Card in it. If you control a monster with ATK greater than or equal to the ATK of the selected Monster Card, destroy the selected card and inflict 500 damage to your opponent. Otherwise, take 500 damage.