The One Ring

Hexproof, indestructible. Can't be countered.
Equipped creature gains abilities if its
base power is: 0-2: Shroud and; 3-5:
Indestructible, double strike, and; 6-9: Lifelink,
vigilance, and; 10+: "When this attacks, tap any
number of target creatures. They cannot untap
while The One Ring is equipped."
Equip: {1}.
Cumulative upkeep: Pay life equal to equipped
creature's base power.