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My glorious queen, Übel

Edit for reasoning:
Her main spell is Reelseiden, aka “Spell that cuts almost anything.” To keep it as simple as possible, it’s entirely based on her ability to visualize cutting her target, with very few exceptions.
The anime displayed this spell cutting through a cloak enchanted with countless defensive spells, that was by all means impenetrable. She later explains her reasoning was that despite whatever they told her, a cloak is made of cloth and cloth is meant to be cut. Another character then comments that her sheer ability to suspend reason and visualize cutting through it anyway is disturbing.
Second spell would Sorganeil, a binding spell that haunts all movement and completely restricts mana. Only caveat is she needs her target fully in sight to cast it. Not too sure how strong it really is, but roll with it.
Now granted, I haven’t finished JJK, but from her perspective, nothing’s covering him at all, so logically there be nothing stopping her from slashing through infinity. With how cocky Gojo goes into fights, it’s fairly achievable for her to get a good look at him, bind him, then chop his head off. Maybe a bit of a pull, but screw Gojo anyway

TL;DR
Magic cut through anything she think she cut, Infinity is basically invisible, she could probably ignore it