Power Stone

Indestructible, Hexproof
Equipped creature gains Indestructible and
"At the beginning of your upkeep add {e}{e}{e}{e}{e}.
Equipped creature gains X power equal to your
number of {e}"
Equip {6} (Equip to Legendary Creatures)
"These carriers can use the stone to mow down entire civilizations like wheat in a field." -The Collector