Mister Gutsies have weapons from the pre-War era, but they are only energy and flame-based. However, they are still tough to defeat because of the material from which they are crafted, which seems to be toughened steel plates.
The hardened Mister Gutsy is significantly higher in damage resistance than the regular Mister Gutsy (on par with the average sentry bot), accredited to their 10 Strength attribute.
The Mister Gutsy prototype is a series of robots and are the prototypes for the Mister Gutsy line, featuring the same weapons and AI but having weaker armor than their production model cousins.
Mister Gutsy units have several weaknesses: they can't use both weapons simultaneously, and will always switch to their flamer when their target is in range, allowing the player character to effectively thwart an attack by continuously entering and exiting flamethrower range, forcing it to constantly switch weapons. Nearby explosions or anything crippling its thruster can temporarily knock it out of the air, giving the player time to strike it down.
Players may also get to point-blank range, as close as possible, and move around the Gutsy. It can't attack while the player is doing this. Getting close enough to do this while avoiding its fire is very tricky.
Mister Gutsies are more resistant to bullets than other robots and armor-piercing rounds seem to have little effect on them. Their voice is also different from the East Coast variants, quieter and tinnier.
Mister Gutsy, unlike the Mister Handy, is a dedicated combat robot and is easily distinguished from the Handy by its olive drab paint job, WWII-era US Army roundel insignia and the replacement of its British butler voice with that of an American drill sergeant's. It was commissioned by the U.S. Army just before the Great War in 2077. They have distinctive "military" personalities, and an advanced AI similar to that of the civilian-model Mister Handy.
These unique Mister Gutsies can be found guarding the crashed vertibird in the southern Mojave, along with hardened sentry bots. Their HP exceeds a regular Mister Gutsy's by fifty points, and their general toughness is on par with the average sentry bot, accredited to their 10 Strength attribute (double that of the average Mister Gutsy).
Mister Gutsy prototype is a weaker version of the regular Mister Gutsy. It uses the same AI and is equipped with the same weapons loadout as the regular series, but its armor is significantly weaker and can be disabled fairly easily. One example of the prototype is encountered when exploring the empty houses in Nipton after the Legion's raid. This Mister Gutsy has already claimed the life of an unwary legionnaire and any unfortunate player may join him, as it is immediately hostile when you enter the house. According to notes on a terminal in the same house, the resident at that time had repaired the robot in order to impress any potential new women in town.
Mr Steels are Mister Gutsy robot derivatives found in New Vegas Steel. Essentially re-painted as Mister Handy robots, they still come complete with plasma projectors and have 100 HP and 25 damage threshold, making them very durable opponents. They use the same skin as a standard Mister Handy.
The Mister Gutsy Mark series only appear in the Fallout: New Vegas add-on Old World Blues. The series runs from Mark 1 to Mark 6 (with the exception of Mark 2, which cannot be found).
Compared to the other Mister Gutsies found in Mojave, the Mark series in Big MT are harder to defeat, their speed and durability being enhanced. They also work with other robotic enemies or appear in numbers.