Card of the Week Poll #365: Everything He Sees is Just Blue

This challenge is inspired by last week's "skyworld" challenge. One of the most common top-down world ideas asked about on Mark Rosewater's blog is a plane that's completely underwater. As he's remarked, it's easy to design blue cards that match the world... but the other colors not so much. That's your challenge: Design a non-Blue card for an entirely underwater plane. No blue mana symbols anywhere!

I expect the color pie to do some heavy bending in terms of flavor. On any other set, your design might look like a blue card. But on an underwater world, there's a blue tint to everything; what matters for determining color is the relative flavor. Still, your card should try to adhere to the mechanical color pie as closely as usual