Ash Nazg

Indestructible
Equipped creature has shroud and it's power and toughness are doubled.

At the end of turn, put a darkness counter on equipped creature. When the number of darkness counters equals a creature's toughness, exile that creature.

When Ash Nazg is equipped to another creature, remove a Darkness Counter and place it on target creature you control.
Equip —Add 2 Darkness counters to creature.