Gasmen are the engineered and chemickally altered Humanoids sealed inside a protective suit and fed with a constant supply of Stimulants & Relaxants to bring them Into & Out of medically induced comas.
Created by Circe Hotchkiss, The Yhathorhm Alchemist created the 'Gasman Mist' as a part of her wildly unethical & widely condemmed Compound Series in 1954. Made by combing many substances such as Compound No.115K, No. 28X, No. 309J, and No. 309Q (often refered to as Krag Silt). The resulting fluid was injected into Volunteers, 'Volunteers' & Deadmen Walking. Whilst the original drug was incredibly flawed (known for it's extensive list of extreme side-effects), it was later refined into a more potent & usable variant by Hotchkiss' team of assistants after she was aprehended by Auld Empire Infiltration Force during the Siege of Yhathorhm.
The later variant of Gasman Mist, as it came to be known, is a liquid at room temperature. However, it becomes a gas at only 34 degrees. This lead to it's original implementation (similair to Lackadaisy) as an Emergency Combat Medication for lengthy and intense battles, with frequent combat encounters. After Lackadaisy was recalled, it was discovered that 'The Mist' was highly adictive and long term use led to increased agreession, degredation of the mind, deformation, and more symptoms that weren't discovered until after The Gasman Suit was deployed.
Following the Assault on Bellevoix, Hotchkiss was retrieved from an Auld Empire Detainment center she had been held in for 11 months. Despite her occasional near Catatonic State, Fleeting bouts of Manic Delerium, aversion to Loud Noises & Touching Bare Skin, constant need for Light, and almost complete change in Demeanor from prior to her capture; was enlisted alongside surving members of her Team of Assistants, Dwarven Alchemists, Sitches Engineers and South Eastern Potalurgists in 'Project: Unstoppable Force'.
The aim of Project: Unstopable Force (or P:UF) was to create a combat worth suit that could utilise The Gasman Mist whilst restraining side-effects, and to improve further upon the chemical cocktail.
The Result of the Project was 'The Gasman Suit'. An Airtight, Reinforced, Padded and Sealed full body suit designed for high intensity melee combat.
The Gasman Suit has a large steel Body/Chestplate that covers the Torso and Head, but not the arms or legs. The Body is fused with the Helmet; which has a reinforced domed glass visor & enough room within to allow for Head movement without moving the Helmet itself. From the back of the Body, several tanks of Stimulants & Relaxants run via a valve and fixed copper pipes to the front of the Helmet, where they connect to the input alongside the output filter which recycles exhaled Drugs.
The Limbs of The Gasman Suit are left mobile by Padded Fabric which covers the joints & leaves the suit more mobile than full plate. The feet are covered by cleated boots and metal shin gaurds, which were implimented after a pattern of slipping whilst running or running into objects during combat was noticed by the suit's designers.
The arms are equiped with a pair of Gauntlets & Vambraces that have wrist mounted hollow spikes, which are connected to a compressor and small gas tank mounted to the forearms. An alternate variant exists with a Ashbrick burning engine, that allows operation of a chainsword.
After their creation, 'Gasmen' as they were dubbed; were deployed typically as Shock Troopers and Rarely as a defence measure in select valuable faccilities.
During the time of thier service 2 things were discovered.
1. Gasmen will eventually require the use of The Mist to breath.
2. The Mist will slowly deteriorate several organs before catastrophic shutdown occurs.
After these effects were discovered, all Training and Creation of Gasmen was ceased.

After the end of The Great Continental War, many Gasmen were left in a state of Limbo. No longer state sponsored, the Gasmen took to performing Mercenary like gaurd jobs where they could alternate between Drug induced comas and Mist fueled service.
The remaining Gasmen became a tight nit community, creating methods to ease thier suffering, repair damage to their suits and create a way for them to move forward into the new era.
One early alteration to the Gasman Suit made by this community was a pump that would faccilitate breathing without the aid of The Mist, whilst in a Coma. Another early discovery was a method to regulate the release of The Mist in the Suit, alowing a higher degree of Mental Clarity. This discovery was made by accident when a, Sgt Major Heath (may he rest in peace) was attempting to perform maintenance on a fellow Gasman and re-attached a pipe to the rebreather filter instead of the Mist disperser, reversing the airflow. The rebreather would redirect a large portion of The Mist back towards the O2 tanks & Resivoirs. With further tinkering, a gauge was installed to allow for a higher degree of control. The main problem with this addition is the that now Gasses are continuously cycled within the Suit before being released via the exhaust vents, introducing a temperature & overheating issue within the suit.
Most Gasmen spend thier Days fliping in and out of a Medically induced Coma, to both preserve their life and slowly dwindling supply of The Mist, which is gradually growing more expensive as the reserved excess grows low. There is currently no known producer of The Mist on Vallen, as it is prohibitably expensive to make.

Each Gasman is Unique. With each Death, thier numbers perminantly dwindle. Eventually, they will be reduced to Memories.