Robotic Control Units, or R.C.U.s, are enemies in Size Matters fought throughout the game. They are technomite robots comprised of a head moved by six spider legs, which control the guard torso and technomite heavy trooper units, and can also take command of gun turret security.
R.C.U.s were first fought by Ratchet and Clank in the Jowai Resort, Pokitaru during "Rescue the girl!" when they were used en masse to attack the resort. The guard torsos they controlled ravaged the resort and captured Luna, with one taking her away to Kalidon. There, they are fought again during "Search the factory", but were only seen outside the factory, whereas on the interior they were always part of the guard torsos. A few where also fought when they managed to eject from the guard torsos at the hidden titanium bolt path at Junkyard LXIV, on Metalis. On the Medical Outpost Omega, they are fought during "Escape the medical facility", alongside medic bots, heavy troopers, and gun turrets.
R.C.U.s comprise a single green humanoid head with yellow eyes and an antenna built on a spider-like body. They have eight limbs, six spider legs used for movement when not controlling a robot, and can also use them to walk on the ceiling, and two small limbs at the front. They only use their head to bite to attack. They are relatively intelligent, as seen in their ability to control numerous technomite robots, but otherwise function in swarms, relying on numbers. During the turret sections in the Medical Outpost they frequently attempted to use debris and objects for cover from Clank while he was controlling the turret.
On Pokitaru and Metalis they would also eject from the guard torso frames when they got destroyed, which they would not on Kalidon or the Medical Outpost. In case of the latter, they were also frequently seen making a run for unmanned gun turrets and stationary heavy troopers, operating them. Gun turrets when operated gained a much higher rate of fire, at the cost of a much slower turning speed.
Robotic Control Units are vulnerable to the OmniWrench 10K, as well as any other weapon due to how weak they are. The Lacerator at first, and later the Scorcher and Suck Cannon, are effectively against single targets and small groups, with the Acid Bomb Glove being better against the larger groups.
- John Aspinwall (February 2007). Ratchet & Clank Size Matters Official Guide Part Three. Sony Computer Entertainment.