When an opponent's monster declares an attack: Target the attacking monster; negate the target's attack, and if you control any face-up Fish-Type, Sea Serpent-Type, and Aqua-Type monsters, inflict 800 damage to your opponent for each of those monsters.
![Poseidon Wave [GENF-EN064] Common](http://www.cardmerchanttakapuna.co.nz/cdn/shop/products/e2d0521f-05ff-5cbb-8f09-7ac450a80daa.jpg?v=1698547186&width=1445)