Mercury(Cessily Kincaid, Marvel)

Mercury is a mutant whose body has permanently transformed into non-toxic liquid mercury. She can stretch and mold herself into different forms like various weapons. In her liquid form, Mercury is resistant to telepathy, she doesn't have to eat or breathe like humans (because she is no longer an organic life form), she is resistant to magic, her molecules can cling to solid surfaces, and she has enhanced durability of her skin, bone, and muscle. Mercury serves on both the first and the second team of Emma Frost's Hellions Squad, and she manages to keep her powers after M-Day.