Sentient Geography

Mana-siphon - Whenever an opponent taps a Land, add that mana to your mana pool.
{4}{t}, Put a Sentience counter on Sentient Geography.
Remove 3 Sentience counters from Sentient Geography and sacrifice it: Search your library or graveyard for a creature card and put it onto the battlefield under your control. It has "When this creature is put into a graveyard, you may exile it instead and return Sentient Geography to your hand."