Cyber wrist blaster

Cyber wrist blasters were Cyber-weapons used by certain variants of Cybermen, either in conjunction with, (TV: The Pandorica Opens) or separate from, (TV: Army of Ghosts) the more common Cyber-guns. (TV: The Tenth Planet et al) Most often used by the Cybermen of Pete's World, (TV: Army of Ghosts, Doomsday) the Cyber Legions, (PROSE: Plague of the Cybermen) the Cyberiad (TV: Nightmare in Silver) and its identical troops that appeared elsewhere in N-Space (TV: Death in Heaven, The Doctor Falls) and the wider multiverse, (AUDIO: Code Silver, Master of Worlds) they were a retractable mounted weapon powered by hydrogen gas and were housed within a Cyberman's forearm.

Characteristics
It consisted of a small segmented steel gun that when about to be used, retracted out of the forearm, extended at the front, then fired a red particle discharge containing an EMP (electromagnetic pulse) that could kill a human almost instantly and penetrate clothing. The gun was connected to the Cyberman's vision circuits to ensure precision in aim. The wrist guns were seen, but not used during the creation of the first Cybermen. (TV: The Age of Steel) They were used during the Battle of Canary Wharf, though the guns were completely ineffective against the force fields of the Daleks as well as the Genesis Ark, leading to many Cyberman casualties during the battle. (TV: Doomsday)

Despite not being able to damage Dalek casings, the weaponry proved effective against other forms of machinery such as robots (COMIC: Drones of Doom) and even other Cybermen. (COMIC: Time of the Cybermen, GAME: Blood of the Cybermen)

However, repeated hits from later Cyber wrist blasters had the potential to endanger Daleks of the New Dalek Paradigm. (GAME: Dalek Supremacy)

Not all of the Cybus Industries Cybermen were equipped with one of the weapons. Amy Pond later noted a slight difference in the appearance of the Cybermen with wrist blasters and those without wrist blasters. (GAME: The Mazes of Time)

The Cyberiad Cybermen recovering from the Cyber-Wars under Hedgewick's World of Wonders had their own variant of wrist blasters, different to that of the Cybus Cybermen. The discharge was blue in colour and the design was far larger and boxy. (TV: Nightmare in Silver) Ashad wielded a similar blaster, the energy of which was drained by time hopping. (TV: The Haunting of Villa Diodati, Ascension of the Cybermen)

The wooden Cyberman sent down to Trenzalore during the Siege had a wrist blaster which doubled as a flame-thrower. (TV: The Time of the Doctor)

In her partially converted form, Lisa Hallett could fire a blast similar to those of the wrist gun however the laser seemed to come from inside her wrist casing instead of from a mounted weapon. This variant could only stun the part of the body which it hit. (TV: Cyberwoman)

The Cyber-Lord in charge of the Cybermen which had crashed at the GSO Arctic excavation site used a Cyber Wrist Blaster to kill Elizabeth Meadows, though the discharge from this blaster was more yellow than that of the other Cybermen. The Cyber-Lord and two of its guards were also killed by a wrist blaster on a detached Cyber-arm used by Chisholm to save the Eleventh Doctor and Amy Pond. (GAME: Blood of the Cybermen)

The wrist blaster was able to be used even if the Cyberman's arm was severed as part of the suit's assimilation protocol and it could rotate. The Cyberman guarding the Pandorica under Stonehenge used the weapon, but the Cybermen accompanying the Cyber-Leader when the Doctor was imprisoned both carried large handheld energy weapons. (TV: The Pandorica Opens)

History
Onboard the Mondasian colony ship, the Cybermen that evolved from Mondasian Cybermen into Cybermen resembling those of the Cyberiad possessed identical Cyber wrist blasters. Although, at first, they did not use them during the battle of Floor 0507, due to their mission parameters being to capture the humans of the floor for Cyber-conversion, following the loss of a large number of troops, the remaining Cybermen began a far greater assault, intent on killing the humans outright. One Cyberiad-type Cyberman attempted to shoot the Twelfth Doctor in close proximity, but was destroyed in a fuel explosion by the Doctor just before it could fire. (TV: The Doctor Falls)

The Cybermen of the Cyber Legions who crashed their ship in 19th century Klimtenburg could have used their wrist blasters against their enemies but the Doctor noted they did not have enough power to use them. Only one Cyberman was able to fire their blaster during the whole incident. (PROSE: Plague of the Cybermen) The Cybermen which were part of the main forces of the Cyber Legions such as the Ninth Cyber Legion and Twelfth Cyber Legion used Energy blasters instead. (TV: A Good Man Goes to War, GAME: The Eternity Clock)

The Cybermen used wrist blasters in attacks on weapons bases operated by Daleks of the New Dalek Paradigm. (GAME: Dalek Supremacy)

The Cyberiad Cybermen recovering from the Cyber-Wars under Hedgewick's World of Wonders had wrist blasters. Alice Ferrin was killed by one of the weapons. (TV: Nightmare in Silver)

The wooden Cyberman sent down to Trenzalore during the Siege had a wrist blaster which doubled as a flame-thrower. The Eleventh Doctor sent a signal with his sonic screwdriver to the device that would have reversed the polarity of the weapon and cause it to fire backwards. The Cyberman turned its weapon around and shot a hole through its own chest, the Doctor neglecting to mention the screwdriver did not work on wood. (TV: The Time of the Doctor)

A trio of Cybermen, including the converted Dr Skarosa, pointed their blasters towards Clara Oswald ready to kill her but hesitated in the case that her claims to be the Doctor were true. They were subsequently destroyed by blaster fire from Danny Pink, who himself had been converted into a Cyberman, before he rescued Clara. Danny later pointed his blaster at Clara when she stated that the Doctor was the best man ever, unknown to her that it was Danny inside the metal man, but hesitated and shakingly lowered it again. The Brigadier, after having been resurrected as a Cyberman, shot with his blaster. (TV: Death in Heaven) However, Missy used the energy from the blaster to recharge her vortex manipulator and escape undetected. (TV: The Witch's Familiar)

The Cyber-Warriors possessed an upgraded wrist blaster powerful enough to destroy weapon implants with a single blow. After upgraded the Warriors into the CyberMasters, they retained their blasters with the Master having one shoot another to demonstrate their regenerative capabilities. When Ko Sharmus threatened to detonate the death particle, the CyberMasters shot him dead only for him to trigger it with his last ounce of strength. (TV: Ascension of the Cybermen/The Timeless Children)