The CK-1 is a quadruped automaton roughly the size and shape of a large dog, built on an articulated chassis that mimics canine locomotion with disturbing accuracy. It weighs 35 kilograms, of which 8 kilograms is a shaped explosive charge housed in its chest cavity. The operational concept is brutally simple: the CK-1 is deployed toward a target, runs at speeds up to 50 km/h across open ground, navigates obstacles using its quadruped agility, reaches the target, and detonates.

Arcturus deliberately designed the CK-1 to look like a dog. This was not an incidental consequence of quadruped locomotion optimization — the chassis proportions, the head shape, even the movement gait were engineered to exploit the human psychological association between dogs and trust, safety, and companionship. In field testing, targets consistently hesitated before engaging CK-1 units, despite being briefed on the platform's nature. The hesitation window averages 1.3 seconds — enough time for the CK-1 to close 18 meters.

The CK-1 is painted matte black with no identifying markings. Some operators have reported that the units occasionally exhibit behavioral patterns that were not programmed — pausing to investigate objects, tilting their heads at sounds, sitting when stationary for extended periods. Arcturus attributes these to emergent behavior in the locomotion algorithm's idle state. The behaviors make the CK-1 more effective, not less, because they make it look more like a real dog until the moment it isn't.