Phyrexian Decimator

Trample
Infect (This creature deals damage to creatures in the
form of -1/-1 counters and to players in the form of
poison counters.)
Spells opponents cast cost {p/b} in addition to its
casting cost for each poison counter on that
player. ({p/b} can be paid with either {b} or 2 life.)
Crew 4