Seahorse Rider

Islandwalk (This creature can't be blocked as long as defending player controls an Island.)
When Seahorse Rider enters the battlefield, create a number of 1/1 blue Fish creature tokens equal to your devotion to blue. (Each Blue in the mana costs of permanents you control counts toward your devotion to blue.)
There are a million fish in the sea, and she knows every single one of them.