Enigmatic workers

{t}: Exile the top card of your library.
{t}: Return target card exiled this way to your hand.
{t}: If there are 6 cards with six different converted
mana costs from 1 to 6 exiled this way,
put a bio counter on this creature. Return all
exiled cards to your graveyard.
Whenever this creature has three or more bio counters on it, you win the game.