Marvel: Retractable Bone Claws

Akihiro (Daken)
Daken possesses three retractable claws housed beneath the skin and muscle of his forearms; two on the top of his hands and one underneath. Daken's bone claws have been shown to be black in color with a very rough texture in contract to the light color and smooth texutre of his father's claws in their natural state. Daken has two claws which emerge from between the skin of his first and third knuckles. These claws are much harder and denser than normal human bone and their natural shape provides them with a razor-sharp edge capable of easily slicing through flesh and bone very easily and are able to penetrate metals as durable as Iron Man's armor.

James Howlett (Wolverine)
Wolverine's skeleton includes six retractable 12-inch long bone claws, three in each arm, that are housed beneath the skin and muscle of his forearms. Wolverine can, at will, release these slightly curved claws through his skin between the knuckles on each hand. The skin between the knuckles tears and bleeds, but the blood loss is quickly halted by his healing factor. Wolverine can unsheathe any number of claws at once, although he must keep his wrists straight at the moment his claws pass from his forearms into his hands. When unsheathed, the claws are entirely within his forearms, allowing him to bend his wrists when they are extended. The claws are made of bone, unlike the claws of normal mammals which are made of keratin, and were originally believed to be bionic adamantium implants. Like his son, Daken, the bone claws are sharp and dense enough to slice through substances as durable as most metals, wood, and stone.

Laura Kinney (X-23)
X-23's skeleton includes two retractable bone claws in each arm and one in each foot that she can extent and retract at will. These claws are housed beneath the skin and muscle. Unsheathing them causes her skin to tear and bleed, but the wounds are quickly dealth with by her healing factor. X-23 can unsheathe any number of these claws at once, although she must keep her wrists and/or feet straight at the moment the claws emerge. The claws are naturally sharp and tougher than normal human bone, allowing her to cut through most types of flesh and natural materials.