Magik, Illyana Rasputin // Darkchild, Demon Uncaged
Legendary Creature — Mutant Sorcerer Hero // Legendary Creature — Mutant Demon Sorcerer
At the beginning of your upkeep, exile the top card of your library. You may play that card this turn. At the beginning of your end step, if you've sacrificed two or more permanents this turn, you may transform Magik.
At the beginning of your upkeep, exile cards from the top of your library until you exile a nonland card. You may play those cards this turn. Pay 4 life: Darkchild gains indestructible until end of turn. Tap her.
Not legal in Commander
Is
View Magik, Illyana Rasputin // Darkchild, Demon Uncaged on Scryfall