Homunculi

A catch-all term for living entities created fully through bio-engineering. While biogenetic technology exists on all planets, Neptune has become a common haven for research and development. This includes:

BYNX: cat-like critters designed to operate in zero-G, with the intent to identify microscopic holes in the hull of vessels. A subspecies exists (Abysgals), which are adapted to survive in harsher or dark environments.

RadCats: an old project to make radiation detectors gone wrong, Radcats are augmented felines intended to glow in the presence of potentially-harmful radiation. Unfortunately, after the 3rd generation, these cats learned to trigger the effect at will. This was discovered when one scientist discovered an escaped experiment in his house in the middle of the night. Cats will be cats.

Slinkies: modified Civets, designed to get into small crawlspaces that nothing else can reach. They take bones optional to a new level, with the distinct ability to (harmlessly) disconnect large portions of their bone structure to slip into the strangest of places.

Coggies: multi-limbed dog-like critters trained to carry tools for mechanics, and perform the most basic of repairs themselves (usually involving duct tape)

Shelmets: aquatic, multi-limbed arthropod with dexterous manipulators to facilitate underwater tool use. Frequently paired with artificial shell for tools storage

Can-air-Es: airborne atmospheric sensors, in constant motion. Their continual chirping indicates all is well. Their avian forms are a constant yellow unless they detect anomalies, at which point they flare in bright red alert colors, and scream a warning klaxon.

Leatherpine: palm-sized rodent, with a wide variety of metallic tools embedded in its body

Antiferno: medium-large critter with in-built firefighting tools. Internal tanks store water for temperature regulation and fire suppression. Natural coat is heat- and fire-resistant, and can be used to suppress or protect.

Mechanical counterparts:

Electric Tuna: mobility/storage aid for octopods. Large, resembling fish. Ridden as a motorized vehicle (ranging from scooter to motorcycle to ATV). Typically brainless, though some varieties have minor automation through SI.

Gec-kits: automated machines designed to patch the hulls of non-atmospheric vessels. Independently mobile with magnetic footpads, and magnetic grapnel stored in the cranium. Upon detecting a hull fracture, the body flattens out into a complete seal. All models use fluorescent colors for high visibility, enabling recovery and permanent hull patching.

Wirefly: insect-based maintenance units for wiring repair

Pluto's Tortoise: shelled quadruped with an internal furnace. Can be used as a mobile heater, grill, or simple campfire.

Pipe Snake: long and thin, designed to bypass conduits during breakage or maintenance. Specific models exist for electricity (micro-model), water (oversized model), hydraulic fluid (mid-scale) and more.