The original robo-scorpion was created before the Great War by Dr. Mobius and his team in the X-42 robo-warfare facility in Big MT, based on scorpions and powered by a fission battery. They were created for security at the Big Mountain Research and Development Center as robotic guardians with a tail-mounted energy bolt blaster, optical systems allowing anyone in the X-42 robo-warfare facility to see through them with monitors, and a self-destruct sequence which, after their death, causes electrical explosion damage to anyone around. Additionally, their public address systems allow anyone in the X-42 robo-warfare facility to speak through them. According to Mobius, they can form themselves from floor panels along with any other random parts lying around. X-42 giant robo-scorpions, unlike the others, were a project for the US military. The entire robot from stinger to pincers is forged from Saturnite and is fitted with atomic laser, but is still susceptible to electromagnetic pulse discharges. Despite several prototypes being requested, certain kinks in design and programming prevented them from reaching battlefield deployment and only one functional prototype was completely finished, remaining idle in the X-42 robo-warfare facility.
Sometime after the Great War, Mobius hacked his colleagues and altered their personalities, chronometers, geometers and more. Disgusted by his own actions against his friends, Mobius erased some parts of his memory to ease his conscience, including the knowledge of his creations. Later, Mobius relocated to the X-42 robo-warfare facility which he renamed the "Forbidden Zone." There, he began to "re-create" the robo-scorpion, now based on the radscorpions which occasionally wandered into Big MT. He added the suffix "b" onto his new creations and retained all features of the pre-War model. He also took control of the previous models of robo-scorpions, making them his personal army. Mobius now uses the robo-scorpions to constantly distract the Think Tank.
The Think Tank eventually came to see the robo-scorpions as evil minions that Mobius was utilizing in an attempt to steal their intellect and stupefy them as a result of his bio-gel negligence and insanity. The group came to rely on Dr. 0's findings that they drained intelligence, due to lack of actual experimentation and inability to "comprehend Mobius' Robo-Schematics," though the reality was that their self-detonation made him unable to study them. Due to this lack of evidence, some did have their doubts on their intellect-draining abilities, seeing them more as nuisances to annoy or irritate them.
Robo-scorpions are very fast and extremely resistant to most damage. Pulse weapons are less effective against them compared to other robots. The X-42 giant robo-scorpion is a special model adorned with Saturnite armor plating, making it virtually impervious to small arms fire, but it is vulnerable against pulse weapons. Its tail is equipped with a powerful atomic laser that draws its energy from an internal generator. The laser is capable of causing severe damage and leaving residual radiation of about 30 rads per second for one second, as well as having a blast radius of about 3 yards. It is also equipped with a self-destruct system like other robo-scorpions, but detonates a small nuclear device instead of an electrical explosion. The X-42 giant robo-scorpion's self-destruct explosion leaves radiation of about 15 rads for the first second which decreases every subsequent second, stopping after five seconds.
Robo-scorpions appear in Mk. 1-5 and Mk.1b-5b (data for Mk. 2 and Mk. 2b exist, but both are unused), and come in a pincer, blaster and bomber variants, as well as different sizes relative to their Mark. Their appearance in the game depends on the player character's level and the importance of the location in which they appear.
The normal robo-scorpions without any special attributes.
“I hope I didn't leave my Giant Robo-Scorpion on. That thing eats power like no tomorrow.”— Doctor Mobius
Encountered in the Forbidden Zone dome during the Old World Blues quest, the X-42 giant robo-scorpion is a unique robo-scorpion and Doctor Mobius' ultimate guardian. It is armed with a powerful atomic laser capable of dealing heavy damage and radiation damage of about 30 rads per second for one second as well as having a blast radius of about that of a pulse grenade. It sometimes fires while one is behind cover, and still causes radiation damage, about 2-15 rads per second.
It is initially claimed by Doctor Klein that robo-scorpions can drain intelligence, with the added humorous context that this information seems to just be Doctor 0 covering for his own incompetence. However, it is later revealed that draining data is an actual function for them.
All robo-scorpions can be disabled with the Robotics Expert perk, including the X-42 giant robo-scorpion. However, the X-42 giant robo-scorpion will restart itself after a set amount of time has passed, a unique feature compared to all other robots.
The X-42 giant robo-scorpion cannot be deactivated with the Robotics Expert perk if it has been put into emergency shutdown.
Robo-scorpions are normally found in groups of up to four.
Mobius stops speaking through them after the completion of Old World Blues.
Even if the Courier teams up with the Think Tank and Mobius after completing the Old World Blues quest, robo-scorpions are still hostile to the player character.
The legs of a giant robo-scorpion, much larger than the X-42, can be seen poking out of the ground next to the Waste disintegration platform. Later, the player character learns through terminals and Mobius' declarations that once a bigger version of the X-42 giant robo-scorpion became frenzied and left the Forbidden Zone and started consuming a lot of energy, so Mobius had to disable and dispose of it.
The X-42 giant robo-scorpion explodes upon death in a similar manner to how Gabe explodes, should he be killed in A Brain's Best Friend. The explosion leaves radiation around and lowers at the same rate as a Fat Man.
As seen in the trailer, X-42 giant robo-scorpion was to appear in Higgs Village, but that encounter was removed in the final release.
The X-42 giant robo-scorpion is the largest enemy the Courier comes across without using console commands.
The robo-scorpion will explode even if melted or disintegrated by plasma/laser energy weapons.
At level 50, the X-42 giant robo-scorpion's health is higher than any other creature in the game.
Quotes are from the robo-scorpions, but are transmitted to the Courier by Mobius through the robo-scorpions' public address systems connected to the X-42 robo-warfare facility.
↑The Courier: "What minions?" Doctor Mobius: "Whoa, have they not constructed themselves yet? That's a bit premature of me. The Robo-Scorpions, of course. They can assemble themselves from floor panels and parts scattered about, quiet inventive - never really know when they might suddenly appear." (Dr. Mobius' dialogue)
↑The Courier: "Why would Mobius want my brain?" Doctor Klein: "WHY DOES HE SEEK OUR DESTRUCTION? WHY DID HE BUILD ROBOT SCORPIONS WITH INTELLIGENCE-DRAINING STINGERS? IT IS BECAUSE HE HASN'T CLEANED HIS BIOGEL IN... A LONG TIME. CLEARLY, HE'S GOT SOME SORT OF PSYCHOLOGICAL CORROSION. HE'S MAD." (Dr. Klein's dialogue)
↑The Courier: "These mechanical Robo-Scorpions "consume" intelligence? Are you certain of your findings?" Doctor Klein: "[SUCCEEDED] DR. O IS CERTAIN OF HIS FINDINGS. AND NO ONE ELSE IN THE THINK TANK IS WILLING TO TEST THE RESULTS. LOSS OF BRAINIAL POWER - TERRIFYING. O HAS SAID ON MANY OCCASIONS HIS INABILITY TO COMPREHEND MOBIUS' ROBO-SCHEMATICS IS BECAUSE OF REPEATED ROBO-SCORPION STINGS." (Dr. Klein's dialogue)
↑The Courier: "Tell me about Mobius and these monsters of his." Doctor 0: "*That "genius" Mobius somehow cobbled together these really impressive-looking robot scorpions with spare parts. Even painted them.* *Tried to see what makes them tick. Can't even examine them without them detonating all over me. Left with shrapnel and burns. Every. Time.* *Supposedly, he has even larger models, even a Giant Robot Scorpion hidden deep within the Forbidden Zone. Yeah, right. Giant monsters. Sure.*" The Courier: "A Giant Robot Scorpion?" Doctor 0: "*Yeah, crazy right? Something right out of a Midnight Science Fiction Feature. Ridiculous. What are the odds?*" (Dr. 0's dialogue)
↑The Courier: "Robo-Scorpions drain intelligence from living creatures - how? Chems?" Doctor Klein: "[SUCCEEDED] I AM NOT CERTAIN. PERHAPS IT ONLY AFFECTS MACHINES. IF SO, YOU MAY BE IMMUNE. IF IT IS CHEMS, THEN WE HAVE NOTHING TO FEAR. SINCE WE ARE AFRAID, IT MUST NOT BE CHEMS AND YOU NEED NOT FEAR, WHICH MEANS YOU CAN TEST IT. LOGICAL." (Dr. Klein's dialogue)
↑The Courier: "These mechanical Robo-Scorpions "consume" intelligence? Are you certain of your findings?" Doctor Klein: "O HAS SAID ON MANY OCCASIONS HIS INABILITY TO COMPREHEND MOBIUS' ROBO-SCHEMATICS IS BECAUSE OF REPEATED ROBO-SCORPION STINGS." (Dr. Klein's dialogue)