[RD/LGP1] Primordial Slash

Your Legend Normal Monsters aren’t going to go down without a fight.

RD/LGP1-JP026 原初の一振り Gensho no Hitofuri (Primordial Slash)
Normal Trap Card
[REQUIREMENT] When your opponent’s monster declares an attack, you can pay 400 LP to activate this.
[EFFECT] The attacking monster loses 700 ATK until the end of the turn. If you control a face-up Legend Normal Monster, you can also choose 1 monster your opponent controls and destroy it.

Source