Crawling Claw
From Crawling Claw. This appears to be nothing more than the paw of a small primate. A closer inspection shows that the hand has been dried by centuries of exposure to... Undead type. This horrible monster is the bane of my existence. The Battle Pet Tamer™ in Crystalsong has one, as does a friend of mine.
The 
Crawling Claw is a battle pet obtained through Archaeology by solving Tol'vir artifacts, appearing as the dried paw of a small primate preserved by centuries in the sands of Uldum.
Guide awaiting review
Farm Tol'vir Fragments
Dig at Archaeology sites in Uldum to collect Tol'vir fragments, or exchange 
Restored Artifacts for 
Crates of Tol'vir Archaeology Fragments from Brann Bronzebeard — both methods take roughly the same amount of time.
Solve the Tol'vir Artifact
Use your accumulated Tol'vir fragments to solve the Crawling Claw artifact, which will grant you an item that teaches the pet.
Buy from the Auction House
If you prefer not to farm, the Crawling Claw can be purchased from other players on the Auction House, though it typically sells for a high price.
Tips
Uldum dig sites share spawn slots with all other Kalimdor dig sites, and only 4 dig sites are active across Kalimdor at any one time, so Tol'vir sites may not always be available.
When fighting the Crawling Claw in pet battles, use an aquatic pet with a critter attack such as a Turtle — aquatic pets take reduced damage from undead attacks, and critter moves deal bonus damage to undead pets.
