Final Tuna and Dolphin King

Flash, Flying, Swimming (This creature cant be
blocked except by other creatures with swimming.)
Final Tuna and Dolphin King enters the battlefield with X +1/+1 counters on it.
Whenever this creature deals combat damage to a player, double the number of +1/+1 counters on target creature you control.
{1}{u}{g},{t}, Remove twenty +1/+1 counters from
Final Tuna and Dolphin King: Take an extra
turn after this one.