Protectron

Protectrons are a type of robot encountered in the Commonwealth, the Island and Nuka-World in 2287.
Background A widespread and popular model in RobCo Industries' line of products, the Protectron was designed as an inexpensive work drone, capable of performing a wide variety of tasks such as construction, firefighting, and office duties. Some models were designed for security and have defensive capabilities.
Characteristics A bipedal, ambulatory robot capable of instigating combat, the Protectron has a transparent faceplate with several blinking red lights within. The dome that serves as their head scans surroundings, and two arms appendages serve as both laser and melee weapons. The upper body of a Protectron can swivel to either side, and can change direction of movement by way of two legs.
Personalities Each Protectron has a programmable personality, each serving a different role. This can be set to default, fire brigadier, law enforcement, medical responder, construction worker or subway steward, by accessing the terminal connected to the Protectron's charge pod. Using this terminal, 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 creatures it attacks:

• 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 un-holsters 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 do not give it a subway token immediately upon request, or do so by way of reverse-pickpocketing.

Variants Protectron 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.
Protectron medic 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. Found outside Robotics Pioneer Park, inside Suffolk County Charter School, Mass Bay Medical Center, Haymarket Mall, Medford Memorial Hospital, Milton General Hospital and Kendall Hospital.
Protectron fire brigadier This Protectron model is equipped with an internal "cryo-gun" which it can utilize in battle. Before the war, it was utilized to suppress fires. Attacking anything near the robot will cause it to become hostile. 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. Found outside the Boston Police rationing site, at Robotics Pioneer Park and inside D.B. Technical High School.
Protectron watcher A somewhat stronger and more powerful variant of the original Protectron, this type can utilize dual laser arms in combat and a better melee attack. It can also appear in several different colors.
Utility Protectron This type can be distinguished by its yellow hazard color scheme with a light on their heads. 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. 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 or mining helmet, the Protectron will note how they are wearing proper safety equipment for the location they are in.
Police Protectron 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 in close range combat.
Protectron guardian Similar to the Protectron and Protectron watcher, this variant is has the highest HP of any regular Protectron. It can use both dual rapid lasers, and has powerful melee attacks.
Protectron devil Protectron devils are Protectrons created by the Rust Devils. They are usually seen in packs with them or other Protectron devils, but are less powerful than their base-game counterparts.
Protectron scourge Protectron scourges are a tougher variant of the Protectron devil, with a stronger melee attack and better laser damage. They are usually seen with Rust Devils or other Protectron scourges.
Doom Protectron Doom Protectrons are an 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 basilisk 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. Their heads are tall, like a spiked crown, with the skull of a human on the lower part. They can be seen accompanying legendary Rust Devils, assaultron gorgons or Mister Handy war machines.
Protectron golem Protectron golems are the strongest of all Protectron variants, with an even deadlier melee attack and even better laser damage. Seen with Rust Devils and accompanying robots.
Nukatron Unique to the Nuka-World amusement park, five variants include Nukatrons, Nukatron watchers, guardians, defenders, and sentinels. They resemble Nuka-Cola machines with a monitor at the top, sometimes playing a "Park Safety Rules" promotional video complete with audio.
Galactron Galactrons are another variant of the Protectron added in Nuka-World in the Galactic Zone. Although marketed as "never-before-seen prototypes", Galactrons are, in reality, customized security Protectrons with a custom white and gold paint job and enhanced laser weapons.
Galactron usher Galactron ushers are meant to provide security during different events.
Galactron watcher Much like the Protectron watcher.
Galactron guardian Equal to Protectron guardians, it is a re-skin of Protectron guardian.
Galactron defender Beefed-up galactron.
Galactron sentinel Identical in appearance to other Galactrons, this variant has the highest stats of the Galactron robot.
Galactron technician The Galactron technician is a Galactron in the projection booth of the Starlight Interstellar Theater. It will initially be in a charging station until the booth is entered.
Gunner Protectron chef This type of Protectron is used by Gunners. The Protectron chef wears a chef hat and is found in the Grandchester Mystery Mansion.
Gunner Protectron Protectrons that have been reprogrammed to be Gunner soldiers.
Protectron sheriff Unnamed Protectron sheriffs are not present in Nuka-World, but Protectrons Sheriff Eagle and Sheriff Hawk do appear in Dry Rock Gulch, manning the entrances as tour guides.