Blood Amalgam

Blood Pact (Whenever a creature with Blood Pact
enters the battlefield, each creature you control with
Blood Pact gets +1/+0 until end of turn and you lose
1 life.)
Whenever a spell is cast from the graveyard or a
token creature enters the battlefield, return
Blood Amalgam from your graveyard to the
battlefield tapped at the beginning of the next
end step.