Lich angels

As this enchantment enters, you lose life equal to your life total. You don't lose the game for having 0 or less life. If you would gain life, draw that many cards instead. Whenever you're dealt damage, sacrifice that many nontoken permanents. If you can't, you lose the game. When this enchantment is put into a graveyard from the battlefield, you lose the game.

You don't lose the game for having 0 or less life. When you have 20 or more life, you lose the game. Whenever you lose life, you gain 2 life for each 1 life you lost. (Damage dealt to you causes you to lose life.)

Flying You can't lose the game and your opponents can't win the game.