One of the most widespread and popular models in RobCo Industries' catalog, the Protectron was designed as an inexpensive work drone, capable of performing a wide variety of tasks from construction, through security, to office duties. It's a compact, bipedal work drone with a pair of manipulators and integrated lasers for self-defense. The large dome contains the primary optic sensors (usually three) and the central processing unit that contains the robot's synthetic personality. For ease of maintenance, the Protectron is typically powered by a fission battery. As it was not intended for combat, at least not as a direct combatant, the Protectron only has a thin alloyed shell meant to protect its internal components from the environment and damage that could be sustained in the course of its duties. The head assembly is typically shielded by a semi-transparent or opaque dome from reinforced glass, though various hardware modifications were introduced before the war to enhance its effectiveness.
Numerous variants of the Protectron were available on the market, due to the its reliability and flexibility. Apart from the standard body, RobCo also offered construction drones with a shielded, reinforced head, emergency light, and internal power tools like nailguns, firefighter models with an internal cryo gun for fire suppression and additional protection from fire and debris, medic units with built-in defibrillators, and reinforced police models with tasers, stronger servomotors, and armored head. Even factory models could be customized with a variety of software and synthetic personalities to enhance its performance, making it a popular choice for both the private and public sectors. These included the R04 V9 "Office Helper" personality with integrated office protocols and scheduling software, RS3 V4.1.6 "Utility Helper" with remote maintenance routine download capability and pest extermination programs, and the RX2 V1.16.4 "Vault Helper", with all the necessary Vault protocols. Protectrons usually came with a special pod, for storage, maintenance, and recharging, and the Standard Protectron Control Interface v2.40 installed on terminals connected to the pod and responsible for controlling Protectrons slaved to it.
The introduction of the Protectron had a deleterious effect on the situation of workers in the United States. The efficiency and reliability of the Protectron made it a fantastic, tireless laborer easily displacing blue-collar workers, even in industries not affected by the ongoing war. Although companies would deny that the introduction of robotic workers was meant to replace human workers, the reality was that any company where Protectrons or other robots were introduced would soon see mass layoffs. In one particular instance, a Pittsburgh steel mill decided to lay off all of its workers citing budget cuts and the need to shut the plant down. When the workers started an occupation strike, the company simply allowed the new Protectron fleet to enter the facility and gun down the striking workers down to the last man.
Unlike protectrons in previous games, the Commonwealth variant (except the police, medic, construction and fire brigadier models) appears to have a transparent "faceplate" made of plastic or glass, with several blinking red lights visible behind the faceplate. It is possible to break this plate by fully damaging the head, which in turn 'blinds' the protectron, reducing its accuracy. If the protectron is inactive and a melee weapon is used, it will increase the chance of breaking the faceplate. Previous versions had an opaque metal faceplate with a lit up glass dome on top.
Protectrons have a glass dome on top of their heads that acts as an ocular lens which allows the protectron to scan its surroundings and act accordingly. In each "hand" is a laser emitter that shoots a high-powered laser. The upper-body of a protectron can swivel up to roughly 90 degrees to either side before having to step into a different position.
All protectrons come with a combat inhibitor mounted on their back that allows them to selectively target opponents. The combat inhibitor is generally left exposed, making it easy to disable when approaching a protectron from behind. When the combat inhibitor is crippled, the robot will fly into a frenzy, automatically engaging the nearest possible target, regardless of any previous affiliation.
Compared to previous games, protectrons have become significantly sturdier, particularly so against ballistic damage. However, by attacking their limbs, their more vulnerable insides will be revealed, which can be attacked for extra damage. If both of the protectron's arms are destroyed, it will initiate a self-destruct sequence. The unit will begin to glow yellow and explode with the force of a mini nuke or a car shortly thereafter.
Protectrons take reduced damage from shots directed at their head. Damage to the rest of their chassis is taken normally. When a protectron has lost a limb arm or leg, its audio system will also be damaged as the robot will speak but with some audio being scrambled.
Legendary protectrons, like other legendary robots, will detonate violently, similar to a mini nuke blast, approximately two seconds after they are destroyed.
In Fallout 4, each protectron has a programmable personality so that it can serve a variety of roles: default, fire brigadier, law enforcement, medical responder, construction worker and subway steward. Personalities can be changed remotely without having to shut down the protectron.
The personality changes the behavior of the protectron, what it says as it patrols, and the creatures it would attack:
Default: Will be any of the five other personalities that are initialized on them.
Fire Brigadier: Attacks anyone carrying weapons (and certain junk items that are fire hazards) in their inventory.
Law Enforcement: Attacks anyone who unholsters their weapon and fires a shot.
Construction Worker: Attacks characters not wearing a work helmet (or any helmet such as the army helmet).
Medical Responder: Attacks any hostile creature and anyone who attacks it first. Will not heal anyone but would "resuscitate" them with electrical melee attacks.
Subway stewards: Attacks hostiles and the player character if they don’t give it a subway token.
To give the subway token to the subway protectron, one must press the action button/key immediately following the bot's request. There is a window of approximately .8 seconds to give the coin (Video Demonstration). Alternatively, you can reverse-pickpocket a coin into the subway protectron's inventory - it will act as though you had given it the token in the .8 second window.
The standard protectron can use its arm lasers to attack foes from a distance, or swat foes away for a substantial amount of damage when up close. If their arms are destroyed, they will initiate their self-destruct sequence and waddle toward their enemies in a last-ditch attempt to take them out. Appears in green, blue and tan.
This model possesses two static electricity generators on its hands which are intended to be used as defibrillators. Protectron medics lack any ranged armament, but are deceptively powerful at melee range. They can attack targets with a staggering flurry of electrified slaps followed by a two-handed power attack.
This protectron model is equipped with an internal "cryo-gun" which it can utilize in battle. Before the War, it was intended to stop fires. If any firearms are fired near it, then it will attack. If the Sole Survivor is equipped with a Molotov cocktail, the protectron fire brigadier (or any protectron set to fire brigadier personality mode) will warn that the item they are holding is possibly a fire hazard and should be disposed of.
This type can be distinguished by its yellow hazard color scheme with a light on their heads. It also has reinforced plating on their heads and backs, originally designed to protect it from construction hazards, but now protect them from whatever they may fight in the wastes. In close range combat, it will attack its target with simple punches. If its target is outside of melee range, it will attack with one or two nail guns (similar to the railway rifle), rapidly firing spikes that can kill even a high level player character with a single shot. It can also be spawned with two cargo loading arms that deal a large amount of melee damage. If the Sole Survivor is wearing a hard hat, the Construction Protectron will thank them for their compliance with the workplace safety rules.
Police protectrons are similar to the utility variants due to the fact that they have reinforced plating over their inner workings. They can be distinguished due to their blue paint job. These protectrons utilize a stun gun or electric shock of some description in close range combat.
Doom protectrons are even tougher variant of the protectron devil, with proportionally stronger melee attack and laser damage. As with the other variants, they are usually seen with Rust Devils or other Rust Devil protectrons.
Protectron basilisks are very high level encounters, with heavily armored chests and legs. They wield a railway rifle in their right arm and a flamer in their short left arm. The right wrist, arm and leg plates are spiked and serrated, causing their melee attacks on targets to leave them bleeding. The left arm and leg plates are reinforced to prevent much ballistic damage. Their heads are tall, like a spiked crown, with the skull of a human on the lower part. Their waist has a standard plate. They can be seen accompanying legendary rust devils, assaultron gorgons or Mister Handy war machines. If prepared, they can take down a behemoth or an integrated tankbot.
A type of protectron unique to Nuka-World. This protectron type shoots weaponized Nuka Cherry/Cola Quantum blasts instead of lasers. Its head and torso are combined into one, with a small screen on the upper torso presumably serving as its primary interface. The screen will sometimes play the "Park Safety Rules" promotional Nuka-World trailer, complete with audio. When this portion is scavenged and put on a robot workbench it removes the option of adding a separate head. Their voices are different than that of a regular protectron, and are much softer and slower.
Identical in appearance to other Nukatrons, this variant has much higher stats and patrols the Galactic Zone of Nuka-World. They have three-and-a-half times the amount of health as the normal Nukatron.
Identical in appearance to other Nukatrons, this variant has the highest stats and patrols the Galactic Zone of Nuka-World. The Nukatron sentinel has four times more health than the normal Nukatron and shoots deadly bursts of weaponized Nuka-Cherry and Nuka-Quantum.
Unnamed protectron sheriffs do not appear anywhere in Nuka-World, but they can still be spawned with the console. However, named protectrons Sheriff Eagle and Sheriff Hawk do appear in Dry Rock Gulch, manning the entrances as tour guides.
Protectron control terminals can be loaded with the protectron override program holotape which gives additional options when linked with active protectrons. There are three options: "Disengage Safety Sensors," "Override Alliance Parameters" and "Hijack VIP Escort Protocols." The first option reverts the protectron to view all entities as hostile, including the Sole Survivor. The second option sets the protectron to be friendly towards the Sole Survivor and any companion(s), and hostile to their enemies. The third option, which appears when the holotape is loaded into a terminal, sets the protectron to be a temporary follower. This option will not be present when loaded into the Pip-Boy, only when loaded on the terminal connected to the charging station.
When hacked to follow the Sole Survivor, protectrons will waddle towards them unfeasibly quickly if they move too far away.
Hacked protectrons do not regenerate health over time.
It is possible to encounter a radioactive protectron. Whatever the logic behind this radioactivity is, the Sole Survivor will take radiation damage from being in close proximity to this protectron whether it is hostile to the Survivor or not. This radioactivity can sometimes interfere with the Survivor's ability to hack the protectron's controlling terminal if the terminal and protectron are in close proximity.
In Robotics Pioneer Park, there are two shacks, one with a leveled deathclaw and one with the four models of protectron in it, and an Advanced terminal. If the latter are set to defend, they will quickly and easily kill the deathclaw.
If the Sole Survivor is wearing a hard hat or mining helmet while a utility protectron is active, the protectron will note how they are wearing proper safety equipment for the location they are in.
↑The Courier: "The display case is empty. The gun's missing." Primm Slim: "Have you gone loco, pardner? I can see the gun with my own three photo sensors from where I'm standing right now. [You hear strange sounds coming from Primm Slim. He may be trying to read a corrupted file, but it would take more science knowledge to be sure.]" (Primm Slim's dialogue)
↑The Lone Wanderer: "Any clue where I can find a Fission Battery?" Butcher: "When we passed the maintenance room, I spied a deactivated Protectron inside. Just wrench open its access panel and you'll find it." (Butcher's dialogue)
↑Supply plant terminals; Terminal, Private Entry #2: "I've managed to delay a rather large shipment of Protectrons today. I told management that we've been having problems with the previous batch of robots and are not prepared for another batch anytime soon. This is complete bullshit of course, the robots work perfectly. They outperform our best worker by a factor of five. The men continue to lose morale day after day. Some blame me, but they don't understand that this is completely out of my hands. I am doing everything I can to help these men keep their jobs. Tom McMullin Supply Plant Supervisor"
↑Supply plant terminals; Terminal, Regarding New Protectrons: "There have been several complaints in the past couple of weeks regarding the new Factory Protectrons installed throughout the plant. Some of you feel this is the first step in the long process of phasing out the human aspect of the plant. Please be assured that this is not our intention. The new Protectrons are here only to protect you, the workers. Also, please remember to carry your ID with you at all times. The Protectrons are programmed to make sure those present in the plant are valid employees. - Management"
↑Supply plant terminals; Terminal, Private Entry #1: "I brought it up with Management today that the men down at the plant aren't taking the new shipment of robots lightly. They fear losing their jobs and I don't blame them. It's my job to make sure morale stays high no matter what happens. It's hard to look each man in the eye and tell him that he has nothing to worry about even though I very well know he'll be unemployed in less than a month. I don't know how long I can continue to lie to these men. Tom McMullin Supply Plant Supervisor"
↑Supply plant terminals; Terminal, Private Entry #3: "Management made a surprise visit to the plant today. I guess they stopped believing what I've been telling them about the robots not performing to standards. They saw first hand the speed and efficiency of the robots. Unfortunately, they also caught two employees in the act of tearing apart a Protectron and smashing it with a sledgehammer. I was to blame of course. The men are starting to believe I'm working closely with the managers and helping them in every way possible to save my own skin. Tom McMullin Supply Plant Supervisor"
↑Supply plant terminals; Terminal, Private Entry #4: "News broke out today over the loud speakers that everyone needs to vacate the plant by 1 PM. "Due to budget cuts, this plant is shutting down." The men knew at once there was no budget cut. They ultimately decided I was to blame, having seniority in this section of the plant. As soon as I heard the news, I grabbed my pistol and made for the exit. It was quickly barricaded. I turned around and ran into this utility closet and locked the door behind me. I'll stay in here until the men go home. Tom McMullin Supply Plant Supervisor"
↑Supply plant terminals; Terminal, Private Entry #5: "The men won't leave. They're determined to wait until I come out. Probably going to give me one hell of a beating, that I'm sure of. I wish they understood how hard I worked for them, how I used every opportunity to delay the inevitable. They better get going though, it's almost 1 PM. The robots will be here in a half hour, sooner if management hears of what's happening. Tom McMullin Supply Plant Supervisor"
↑Supply plant terminals; Terminal, Private Entry #6: "I begged them to leave before the robots got here. They laughed and said they'd take care of the robots, it's me they wanted. Then came the familiar rattle of a Protectron. That got their attention. I soon heard laughter, cursing, and screaming down the hall. I opened the door and stepped outside. A couple of the workers burst around the corner screaming for help. A red laser lashed out from down the hall and severed Tim's right arm in two. I panicked and ran back into the closet and shut the door. The men slammed into the door and begged me to open it. I didn't say a word, just sat stunned, listening to their screams of agony as the robot finished them off one by one. Then silence. I put my ear to the door and listened. I heard the clanking of Protectron feet down the hall. I grabbed my pistol and backed away from the door. No way am I opening this door for anyone or anything! Whoever reads this, let it be known that I did everything in my power to keep everyone's job at the plant. And let this be an example of how not to replace humans with machines. Tom McMullin Supply Plant Supervisor"