Glacier Aqua Madoor (DAMA-EN023) - Dawn of Majesty 1st Edition

At the start of the Damage Step, if your Normal Monster battles an opponent's monster: You can reveal this card in your hand; discard 1 card, and if you do, your monster cannot be destroyed by that battle. At the start of the Damage Step, if this card battles an opponent's monster: You can reveal 1 Normal Monster in your hand; discard 1 card, and if you do, destroy that opponent's monster.