Thrull Parasite 
Creature — Thrull
Extort (Whenever you cast a spell, you may pay 
. If you do, each opponent loses 1 life and you gain that much life.)
, Pay 2 life: Remove a counter from target nonland permanent.
Legality
standardNOT LEGALpioneerLEGALmodernLEGALlegacyLEGALvintageLEGALcommanderLEGAL