Sailfin Lungquencher

Submerge (You may have this creature enter the battlefield with a -1/-1 counter on it. It can't be blocked as long as it has a -1/-1 counter on it.)
{t}, {u}{b}: Put a flood counter on target creature.
Whenever Sailfin Lungquencher deals combat damage to a player, put a -1/-1 counter on each creature with a flood counter on it.
"Humans can breathe water. Briefly."