Fell Cogriv

Infect, shroud (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters, and it
can't be the target of spells or abilities.)
Fell Cogriv isn't a creature unless a creature
you control has been targeted this turn.
{t}, Sacrifice Fell Cogriv: You draw X
cards and lose X life where X is the number
of other creatures you control.