Korlis Life Reversal

All creatures have vigilance. At the beginning of each player's end step, tap all untapped creatures that player controls that didn't attack this turn. This artifact deals damage to the player equal to the number of creatures tapped this way.

Sacrifice this creature: You gain life equal to the life you've lost this turn. (Damage causes loss of life.)

Play with your hand revealed. If you would draw a card, reveal the top card of your library instead. If it's a creature card, put it into your graveyard. Otherwise, draw a card. Whenever a creature is put into your graveyard from the battlefield, return it to your hand.

If you would gain life, you gain twice that much life instead.