X-Men #14 [2020]

Within this story, Genesis speaks of his sister, Isca the Invincible, and reveals that not only did Isca defect to the Amenthi side in the battle between the Amenthi and Arakko, but she also abandoned Isca's mutated power: she literally cannot be defeated. That's her power, she will always adapt to the battle in a way that will always make her win. It's a crazy power for sure - one that feels a lot more broken than Domino's probability-altering power, as Isca seems to adapt rather than the situation - but just how troublesome this power is starts to become clear in Marauders #14 At the pre-battle dinner, the X-Men try to size up their opponents, looking for weaknesses they can use to their advantage in the next fight. However, when Magik and Gorgon try to figure out what makes Isca tick, they discover that she doesn't have a "weak spot" that they can figure out, and may not have any.