Hermit's Geode

Hideaway (This artifact enters the battlefield
tapped. When it does, look at the top four cards of
your library, exile one face down, then put the rest
on the bottom of your library.)
{1}, {t}: Put a charge counter from Hermit's
Geode. Then if there are three or more counters
on it, sacrifice Hermit's Geode and play the exiled card without paying its mana cost.