Soul Drain Dragon

Cannot be Normal Summoned/Set. Must be Special Summoned by a Dragon-Type Xyz Monster's effect in your possession, and cannot be Special Summoned by other ways. When Special Summoned, if your Life Points are lower than your opponent's: This card gains ATK equal to your current Life Point deficit, and if it does, your opponent takes no further damage this turn. This card cannot attack your opponent directly.

Dragon LIGHT Effect Monster 8 effect