Grila, Weapons Magnate

All Artifacts are Treasures in addition to its other
types with "{t} Sacrifice this artifact: Add one
mana of any color"
When a treasure is sacrificed for mana, if it cost
4 or more, its controller creates two treasure
tokens
Sacrifice X treasures: return target artifact with
cost X or less from your graveyard to the
battlefield. Any player may activate this
ability