"Alright, we got seven canisters of CN-20. I say we roll them in there and nerve gas the whole fucking nest."
"That's worth a try, but we don't even know if it's gonna affect them."
―Pvt. Vasquez and Cpl. Hicks
CN-20 Nerve Gas

A canister of CN-20 Nerve Gas.[1]

CN-20 Nerve Gas[1] is a highly toxic and potent submission gas used by the United States Colonial Marine Corps to take out enemies via submission through neurotoxic gas.[citation needed]


As the name suggests, CN-20 Nerve Gas attacks the nervous system of the human body. All such agents function the same way: by interrupting the breakdown of the neurotransmitters that signal muscles to contract, preventing them from relaxing. Initial symptoms following exposure to CN-20 are a runny nose, tightness in the chest and constriction of the pupils. Soon after, the victim will then have difficulty breathing, and will experience nausea and drooling. As the victim continues to lose control of his or her bodily functions, he or she will involuntarily salivate, lacrimate, urinate, defecate and vomit. This phase is followed by twitching and jerking, and ultimately the victim will become comatose and suffocate as a consequence of convulsive spasms. The effects of nerve agents are very long lasting and cumulative (increased successive exposures), and survivors of nerve agent poisoning almost invariably suffer chronic neurological damage.[citation needed]

The Nerve Gas is stored in 20 litre canisters and is released by setting a timer switch on top of the drum this can be set from 2 minutes up to 24 hours. When the countdown is reached the drums lid automatically slides open and begins depositing the nerve gas into the surrounding area. One drum can cover an area of approximately 200 metres and can spread quickly depending on wind, if no wind is present the gas will move at approximately 5 metres every 10 seconds. Dissipation again depends on wind; high wind can cause it to dissipate after 20 minutes. If no wind is present the gas can stay in an enclosed area for anything up to 10 days.[citation needed]

Behind the scenes

In reality, CN is a designation for phenacyl chloride when it is used as a riot control agent. Like CS gas, CN irritates the mucous membranes (oral, nasal, conjunctival and tracheobronchial). Sometimes it can give rise to more generalized reactions such as syncope, temporary loss of balance and orientation.

At high concentrations CN has caused corneal epithelial damage and chemosis. It has also accounted for at least five deaths, which have resulted from pulmonary injury and/or asphyxia.

Today, CN gas has largely been supplanted by CS gas, but it is still supplied to paramilitary and police forces in a small pressurized aerosol known as “Mace” or tear gas; its use is falling as pepper spray both works and disperses more quickly than CN.




  1. 1.0 1.1 Aliens/Predator Collectible Card Game — 59. CN-20 Nerve Gas (1997), HarperPrism.
  2. "Trade Cards Online - CN-20 Nerve Gas". Retrieved on 2014-12-27.