Enduring Angel (17) [Innistrad: Midnight Hunt]

Flying, double strike
You have Hexproof.
If your life total would be reduced to 0 or less, instead transform Enduring Angel and your life total becomes 3. Then if Enduring angel didn't transform this way, you lose the game.
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Angelic Enforcer
Flying
You have hexproof.
Angelic Enforcer's power and toughness are each equal to your life total.
Whenever Angelic Enforcer attacks, double your life total.