A Single Rubber Duck

Islandwalk, hexproof
A Single Rubber Duck enters the battlefield with
X +1/+1 counters on it
{u},{t}, Remove a +1/+1 counter from A Single
Rubber Duck: Put a number of squeak counters
equal to the number of Islands you control on
A Single Rubber Duck. At the beginning of
the next end step, if A Single Rubber Duck has
ten or more squeak counters on it, you win
the game.