Pierson's Puppeteers are described by Niven as having two forelegs and a single hindleg ending in hoofed feet, and two snake-like heads instead of a humanoid upper body. The heads are small, containing a forked tongue, rubbery lips rimmed with finger-like knobs, and a single eye per head. The Puppeteer brain is housed not in the heads, but in the "thoracic" cavity well protected beneath the mane-covered hump from which the heads emerge. They use the "mouths" to manipulate objects, as a humanoid uses hands.