Marrow

Marrow is the alias of a mutant named Sarah from Marvel Comics.

Powers
Hyper-accelerated metabolism: Marrow's metabolism is the basis of what fuels her abilities to the way that they have manifested. Dual hearts: She also possessed two hearts to compensate for her random bone growth. Therefore, when Storm ripped out one of her hearts, she was able to survive. It's possible that the first heart could have regrown due to her healing factor.
 * Accelerated bone growth: Marrow has the ability to control the growth, shape, and toughness of her bone structure. Initially, this was uncontrolled as they constantly protruded from her skin at an uncontrollable rate but, after enhancement by a Skrull medical facility and later by the Weapon X Program, she learned to mostly control it and retain a more cleanly semblance. Marrow's body generates bony protrusions which she can remove, though not without pain, and wield as weapons. These bones can act as a form of protective shielding or armor by covering herself with it. She can utilize this power in many ways, including the creation of knuckle guards, spears, blades, rigid tendrils, bone claws, finger and knuckle protrusions, adn even projectile spikes. While with Weapon X, Marrow had more control of her protrusions and was able to hide them, appearing normal and form more complex shapes and of a higher quality similar to ivory. After having regained her powers, she regained complete control over her power, strengthening it at the cost of her sanity.
 * ​Bone structure durability: Her skeleton seems to be more durable than normal; she has easily survived heavy hits on several parts of her body. For example, Flag-Smasher hit her twice with his mace on the head without creating much damage and Sabretooth threw her against a wall with no result on her inner bones.
 * Regenerative healing factor: She is able to heal from the wounds she gives herself while removing the bones from her body. Her healing factor also grows her bones quickly and regenerates her bones when they need to be replaced.
 * ​Enhanced strength
 * Enhanced agility
 * Enhanced reflexes

Abilities
Marrow is proficient at using blade-shaped bones as throwing weapons or in hand-to-hand combat. Marrow is an expert hand-to-hand combatant, specializing in street fighting.