Fountain of Blood

When Fountain of blood enters the battlefield you may sacrifice any number of creatures. You create a blood token for each creature sacrificed this way.

When you draw a card from sacrificing a blood token, you may draw a second card.

Sacrifice {x} Blood tokens: create an X/X Eldrazi Vampire token with trample, lifelink, and "When this creature deals damage to a player, create that many blood tokens".