"Since Hypno-Disc has come on the scene, people have started building very powerful spinning discs"
— Martin Smith

Horizontal flywheels are a type of heavy rotating weapon, and among the most famous and destructive weapons in Robot Wars. The pioneer - and most successful example - was Hypno-Disc in Series 3, who inspired numerous derivatives and imitations in later series. Despite this, apart from Hypno-Disc, only 13 Black, Destructive Criticism, Botwork, and to a lesser degree; Disc-O-Inferno and Supernova, also achieved considerable success with this weapon type, with other competitors suffering from inexperience.


  • A flywheel is a comparatively heavy disc weapon that spins at high speeds. One or more 'teeth' are welded or integrated into certain parts of the disc with the intention of gouging, tearing and concussing other robots.
  • These flywheels were mounted horizontally, to leave gashes in the sides of other robots as well as ripping off whole armour sections and tearing off exposed components such as wheels.

Advantages and DisadvantagesEdit


Hypno-Disc Stealth

Hypno-Disc destroys Stealth's flipper

Supernova vs Ming 3

Supernova tears through Ming 3's self-righting mechanism

Bulldog Breed vs Hypno-Disc

The gyroscopic forces of Hypno-Disc's disc allowed it to remain upright after being flipped by Bulldog Breed in Series 6

  • Horizontal kinetic flywheels are amongst the most destructive weapons, capable of slashing, tearing and ripping off components and entire sections of armour, as well as knocking opponents out in one blow. Hypno-Disc was especially notable for this throughout its appearances, effectively destroying robots such as Robogeddon, Stealth, V-Max and Splinter, as well as landing one-hit knockout blows to Firestorm 3 and Barber-Ous 2.
    • They are even capable of causing enough damage to force opponents to retire and withdraw from future battles. Atomic 2, Bulldog Breed 3 and Steg-O-Saw-Us were all forced to forfeit places in battles held after their defeats against Hypno-Disc due to the damage the latter inflicted on them, whilst Team Velocirippa had to build a new model of Velocirippa after the original was severely damaged by Disc-O-Inferno.
  • These flywheels, as with horizontal heavy rotating blades, can provide the robot with a large degree of protection from the front or sides, making it difficult for opponents to attack the robot from where the disc was positioned.
  • A horizontal flywheel offers a larger attack area than its vertical counterpart, offering them a considerable advantage over vertical flywheels.
  • These types of flywheels are easily compatible with an invertible design, with Disc-O-Inferno, Supernova and DisConstructor being among numerous examples of this. Indeed, in Series 7, only three of the fourteen entrants wielding horizontal flywheels were not invertible.
  • Depending on their size and power, the gyroscopic forces of a horizontal flywheel can prevent the robot wielding it from being flipped over when the weapon is spinning, in a similar way to horizontal bar spinners. This was demonstrated during Hypno-Disc's Series 6 battle with Bulldog Breed, where the gyroscopic forces of its flywheel allowed it to land on its wheels when it was thrown into the air by the latter.


Discoinferno refbot

Disc-O-Inferno catches fire en-route to victory against Killer Carrot 2

Disc is stopped

Hypno-Disc's disc lies dormant after Shunt axes through it


Supernova hurtles towards the pit after losing its teeth and being angled by TR2

  • To make flywheels powerful, it was necessary for the disc to take up a significant amount of the robot's weight. Robots such as Supernova and Topbot were forced to wield less durable armour and have small holes drilled through the disc, wheels or armour in order to keep them within the weight limit.
  • As with other heavy rotating weapons, the higher kinetic energy of a horizontal flywheel, and increased power required for them to function, can reduce the reliability of a robot's weapon. This factor caused most of Hypno-Disc's defeats throughout its appearances, as did Disc-O-Inferno's near-loss in Series 6 to Killer Carrot 2.
  • Horizontal flywheels often have a pronounced gap between the disc and the part of the chassis where they are mounted, which can allow them to be hooked from underneath by lifting or flipping weapons. A-Kill and Devastator were especially susceptible to this issue.
  • These flywheels are especially vulnerable to getting stopped or severely damaged by overhead weapons. Shunt's axe blow on Hypno-Disc during its Series 4 Grand Final battle with Pussycat was enough to not only stop the disc, but also leave a hole through its cover and cause severe damage to the robot's gearing.
  • The gyroscopic forces of a flywheel can adversely affect the robot's control and stability, particularly when spinning at full speed. Supernova's flywheel was notable for aggravating the robot's control problems whenever it was damaged or positioned at an angle, once carrying it towards the pit in Series 8 after losing its teeth and being positioned on its side by TR2.


  • In Series 7, eleven of the fourteen horizontal flywheels lost in Round 1, and only S.M.I.D.S.Y., featuring the smallest flywheel, made it to the Heat Final stage.

List of Robots with Horizontal FlywheelsEdit


13 Black



Destructive Criticism

Destructive Criticism



Discontructor 2016








Supernova S9



The Cat

Tornado Frame

Tornado with its flywheel from US Season 2

Trouble n strife

Trouble 'n' Strife


Twisted Metal


Unibite 2.0

Wildthing s5

Wild Thing in Series 5

Robots are listed alphabetically. Robots which are not heavyweight entries are listed with a green background.

Robot Series Appearances with Horizontal Flywheels Notes
13 Black Series 5-7, Extreme 2 Had two flywheels, one resembling a roulette wheel, the other with the number 13 painted on it. Was capable of "walking" on its discs whilst inverted. Series 6 Semi-Finalist.
A-Kill Series 6 Was described by Jonathan Pearce as looking like 'two dustbin lids squashed together'.
Botwork Dutch Series 1 Dutch Series 1 Grand Finalist.
Chip Extreme 2, Series 7 Forced to replace with a static spike after the disc broke in Extreme 2.
Coffin-Bot Extreme Warriors, Season 1
Demolition Man Series 7 Flywheel could move to act as a srimech.
Destructive Criticism US Season 2, Nickelodeon US Season 2 Grand Finalist.
Devastator Series 7
Direct Action Extreme 2
Disc-O-Inferno Series 4, 6-7, Extreme 1 Extreme 1 Annihilator Champion.
DisConstructor Series 7-8 Disc was mounted at a 15-degree angle.
Double Trouble Series 6 Had two small motorcycle flywheels located side-by-side, similar to Shredder.
Dragbot US Season 2
Expulsion Series 9 Flywheel made out of 10mm military grade steel and features four retractable teeth which emerge from the disc as it spins. Able to spin in forward and reverse directions.
Hodaf The Bad Series 7
Hypno-Disc Series 3-6, Extreme 1-2 First and most notable robot with a horizontal flywheel. Three-time Grand Finalist and winner of the Most Original Entry award in Series 3.
MaxiMill Dutch Series 1, Extreme 1
Mayhem Series 7
Mazakari Series 4 Had to cut holes in the flywheel as the machine came in overweight.
Militant Extreme 2 The only non-heavyweight with a horizontal flywheel.
Ninjitsu US Season 2, Nickelodeon A square-shaped disc with four teeth.
PP3D Series 8-9 An 'undercutting' HARDOX flywheel, mounted beneath the robot's chassis and weighing 31kg. Built by Gary Cairns.
S.M.I.D.S.Y. Series 5-7, Extreme 1-2 Heat Finalist in Series 4, 5 and 7; also wielded jaws in Series 3-5 and a lifter in Series 6-7. It relied more on these weapons, along with its pushing power, to win battles.
Scorpion Series 6-7 Competed in Series 6 as Spirit of Scorpion.
Short Circuit Series 6
Spin Doctor US Season 2
Supernova Series 5-9 Runner-up in The Third World Championship. Disc weighs 22kg and spins up to 2,500rpm as of Series 9.
The Cat Series 9 Competed exclusively in Battle of the Stars
The Scrapper Series 7
Tip-Top Series 5 Used the gyroscopic forces from its disc to move the robot.
Topbot Series 7 Powerful enough to smash the arena wall.
Tornado US Season 2 Mounted on a metal frame surrounding the robot, as part of an 'anti-crusher weapon' designed specifically to fight against Razer. Only used once in the Extreme Warriors Season 2 International Championship, before being replaced with a horizontal rotating blade for Series 6 and Extreme 2.
Trouble 'n' Strife Series 5 Rear-mounted flywheel combined with a rear-hinged flipper at the front.
Twisted Metal Dutch Series 1-2 Dutch Series 1 Grand Finalist. Competed in Dutch Series 2 as Twisted Metal EVO.
Unibite 2.0 US Season 2 Replaced the large cutting disc weapon used by the original Unibite.
Vortex Inducer Dutch Series 2 Mounted on an arm which could twist in either horizontal or vertical positions.
Wild Thing Series 5 Disc was fixed at a 45-degree angle.
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