Stormbringer, Who Eats Souls

Equipped creature gets lifelink and deathtouch.
Whenever equipped creature destroys another
creature in combat, put a charge counter on
Stormbringer, Who Eats Souls. Equipped
creature gets +1/+1 for each charge counter
on Stormbringer, Who Eats Souls.
At your upkeep, pay {x} or sacrifice equipped
creature, where X is the number of charge
counters on Stormbringer, Who Eats Souls.
Equip/Unequip {4}