Malenia, Goddess of Rot

Lifelink, vigilance, wither
Scarlet Aeonia - While attacking, Malenia, Goddess of Rot gains flying and trample. When Malenia deals combat damage to a player, each opponent takes that much damage. When Malenia deals combat damage to a creature, each other creature takes that much damage.
When a player dealt damage by Malenia this turn loses the game, exile her, then return her to the battlefield tapped and under her owners control.