The KS-11 is a small, four-legged spider platform the size of a large tarantula, carrying a single hyper-velocity penetrator round in a dorsal-mounted miniaturized railgun. The unit positions itself at range — typically on a wall or ceiling with line of sight to a doorway, corridor junction, or anticipated target position — and fires a single shot with sufficient velocity to penetrate standard body armor at ranges up to 50 meters. After firing, the unit has no remaining offensive capability and either self-destructs or withdraws for reloading.

The KS-11 is a mechanical sniper the size of a hand. It can be placed in locations no human sniper could access — inside ventilation grates, on the underside of furniture, behind wall panels — and wait indefinitely for a target. The railgun produces a sharp crack and a brief electromagnetic pulse on firing, but the unit's size and position make locating the source extremely difficult. By the time the shot is traced, the KS-11 has either destroyed itself or scuttled to a new position.

Arcturus produces them in bulk and sells them as 'perimeter denial micro-platforms.' A facility protected by fifty KS-11 units has fifty invisible snipers covering every corridor and doorway. The cost per unit is low enough that they can be treated as disposable — fired once and abandoned.