Search your library for a basic land card, put it onto the battlefield tapped, then shuffle. Create a 0/1 colorless Eldrazi Spawn creature token. It has "Sacrifice this creature: Add {C}."
Target creature gets +1/+1 until end of turn for each creature you control.
The Joraga elves never need ask a troll to leave their territory. They merely grant it their combined strength, and it can't resist embarking on a merry rampage.
As an additional cost to cast this spell, sacrifice a creature. You draw cards equal to the sacrificed creature's power, then you gain life equal to its toughness.
It wasn't long until the elves had developed a use for every part of the Eldrazi.
Play with the top card of your library revealed. As long as the top card of your library is a creature card, Mul Daya Channelers gets +3/+3. As long as the top card of your library is a land card, Mul Daya Channelers has "{T}: Add two mana of any one color."