The HC-2 is a squat, disc-shaped cleaning platform roughly a meter in diameter that navigates residential spaces on six stubby rubber-padded legs. It vacuums, mops, scrubs, and sanitizes — switching between cleaning heads stored in a rotating carousel on its underbelly. The legs give it the ability to climb stairs, navigate furniture, and reach into corners that wheeled cleaners cannot. It maps its environment on the first pass and optimizes subsequent routes for efficiency, returning to its charging dock when battery drops below fifteen percent.

Hearthstone sells millions of these annually. They are the most common automaton in GLMZ by a factor of ten. The HC-2 is so ubiquitous that most people forget it is a machine at all — it becomes furniture, background noise, part of the architecture of daily life. This ubiquity makes it a favorite platform for aftermarket modification. Gray-market firmware allows the HC-2's onboard camera (intended for obstacle detection) to stream video to remote terminals. An estimated one in forty HC-2 units in GLMZ has been modified for surveillance without the owner's knowledge.

Hearthstone's warranty explicitly states that the HC-2 is not a pet, not a companion, and not alive. This has not stopped a thriving industry of aftermarket personality modules that give the unit chirping sounds, bumbling movement patterns, and the appearance of curiosity. People name them. People mourn them when they break.