Unearthly Grip. While this claw is grafted to you, you can make unarmed strikes with it. On a hit, you deal 1d8 slashing damage instead of the normal damage granted by an unarmed strike. You can also telepathically communicate simple images to creatures you touch with this claw, though you have no special ability to understand them in return.
Optional Attunement. You can also attune to this claw while it is grafted to you. If you do, you gain the following benefits

Your Strength score increases by 2, up to a maximum of 21, unless it was already higher.
You can use a bonus action to deal 1d8 psychic damage to a creature you have grappled with the claw.
You are immune to the blinded condition, thanks to the claw's eldritch eyes.