Thorn

Thorn is an Earthling villain who has a thorn-like growth that can retract into her body and come back out at any other part of her body instantaneously. This thorn can only be at one part of her body at a time, but it is virtually indestructible and can slice through almost anything, making Thorn very difficult to contain by anything short of two pairs of self-repairing handcuffs, or maybe a box surrounded by lava. She normally stays in Atlanta and does small-time crime, but since her "thorn in the flesh" is superpower-grade, she's had some run-ins with I.C.T.H.I.S.