Demise, king of Armageddon

menace, deathtouch
Whenever a creature an opponent controls
dies, you gain 1 life and each opponent loses 1 life.
If Demise entered the battlefield this turn, it has indestructible.
{3}{w}{b},Sacrifice a creature: Destroy all other creatures.
Each player loses life equal to the total power of creatures they controlled destroyed this way.