Korsaiya, The Sovereign Seas

Islandwalk, Resurface, Flash
Resurface - when a creature you control with resurface leaves the battlefield, you may remove a flood counter from target land you control to return that creature to the battlefield under your control)
Sea creatures are Krakens, Leviathans, Octopus, Serpent, Fish, Shark, Whale and Jellyfish.

When a Sea Creature enters the battlefield, you may put a Flood Counter on target land.
When there are seven or more Flood Counters on lands, Sea Creatures you control