Malenia, Blade of Miquella

Double Strike, Vigilance, Hexproof
Scarlet Rot - At the beginning of each upkeep,
but a -0/-1 counter on each creature.
Whenever this creature does combat damage to a creature, regenerate.
When this creature dies for the first or second
time, return it to the battlefield. When this
creature dies for the third time, return it to the
battlefield transformed.