Knights' Charge 
Enchantment
Whenever a Knight you control attacks, each opponent loses 1 life and you gain 1 life.
, Sacrifice this enchantment: Return all Knight creature cards from your graveyard to the battlefield.
Legality
standardNOT LEGALpioneerLEGALmodernLEGALlegacyLEGALvintageLEGALcommanderLEGAL