Raven of Blood Vision

Blood Pact, flying
As long as red is the most common color among
all permanents or is tied for most common,
creatures you control have 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.
Multiple instances of Blood Pact does nothing.)