The Skofnung Sword

Equipped creature has +2/+2 and Blood Lust 2
(When this equipped creature deals combat damage to
a player or destroys a creature put two +1/+1 counters
on it.)
Equipped creature deals damage to creatures
as -1/-1 counters.
Equip {1}{p/u}{p/b}
Equip {u/b} sacrifice a creature