Fenrir, bringer of death

Trample, haste, indestructible
insatiable hunger- whenever a creature an
opponent controls dies, put {x} +1/+1 counters
on Fenrir, bringer of death
Harbinger of Ragnarok- at the beginning of each
opponents upkeep, they may either choose to sacrifice a creature,
or lose life equal to Fenrir's power

Aww, he's so fluffy! -gronk the strong, last words