Darksteel Monolith 
Artifact
Indestructible
Once each turn, you may pay 
rather than pay the mana cost for a colorless spell you cast from your hand.
Legality
standardNOT LEGALpioneerNOT LEGALmodernNOT LEGALlegacyLEGALvintageLEGALcommanderLEGAL
Artifact
Indestructible
Once each turn, you may pay rather than pay the mana cost for a colorless spell you cast from your hand.