Birthday for Grandpa

Shroud, Indestructible
{x}{t}: Put X birthday counters on Birthday for
Grandpa.
Whenever Birthday or another
permanent enters the battlefield under your
control, put a birthday counter on Birthday
for Grandpa and reveal the top card of your
library. If it's a permanent card, put it onto
the battlefield under your control. If Birthday
for Grandpa has 61 or more birthday counters
on it, you win the game.