Esper Sentinel 
Artifact Creature — Human Soldier
Whenever an opponent casts their first noncreature spell each turn, draw a card unless that player pays 
, where X is this creature's power.
Legality
standardNOT LEGALpioneerNOT LEGALmodernLEGALlegacyLEGALvintageLEGALcommanderLEGAL