Stinging Study 
Instant
You draw X cards and you lose X life, where X is the mana value of a commander you own on the battlefield or in the command zone.
Legality
standardNOT LEGALpioneerNOT LEGALmodernNOT LEGALlegacyLEGALvintageLEGALcommanderLEGAL
Instant
You draw X cards and you lose X life, where X is the mana value of a commander you own on the battlefield or in the command zone.