Steel Cobras

Steel Cobras
Battle Cry Unknown
Origin 23rd Founding
Warband Leader Unknown
Base of Operations Tukareo VII
Strength Unknown
Specialty Surviving in liquid ammonia, apparently.
Allegiance Chaos Undivided, though Nurgle is probably scouting them out.
Colours Brazen Brass with Dark Angels Trim

Wow-wee, the Steel Cobras, sounds like the name of a biker gang. Made during the 23rd Founding, these guys were tasked with supporting the Imperium in places where it needed the help. Sadly, the Cobras got a visit from the Ecclesiarchy, and when the leader saw how the Cobras worshipped the Emperor via animal totems, he got his Excommunication on. Sounds familiar, no? From there, the Steel Cobras joined Chaos, and now have probably the most insane hideout outside whatever the Alpha Legion uses the most. Their base of operations is a set of seabunkers on the bottom of an ammonia ocean on the icy world of Tukareo VII. What makes this even funnier is that the Imperium knows they're there, it's just they won't commit the resources, let alone an entire chapter, to go down there and fish them out. No reason why they don't just Exterminatus the planet, though; if your planet is cold enough to have liquid ammonia, you're beyond a Death World. This could, as in it should, mean that these guys are Water Marines. Or, more likely, hazardous environmental operation marines...or hilariously, Piss Marines. Sadly, this is the entirety of their fluff, and they only had a picture of a mini from the 3.5 Chaos Space Marine codex.

The Traitor Legions of Chaos
Chaos Legions: Alpha Legion - Black Legion - Death Guard - Emperor's Children
Iron Warriors - Night Lords - Thousand Sons - Word Bearers - World Eaters
Warbands: Apostles of Contagion - Bloodborn - Blood Gorgons - Broken Aquila - Company of Misery
Crimson Slaughter - Disciples of Destruction - Dragon Warriors - Extinction Angels
Foresworn - Lords of Decay - Plague Fleet - Prodigal Sons - Punishers - Red Corsairs - Sons of Malice
The Brazen Beasts - The Consortium - The Flawless Host - The Purge - The Reborn
The Scourged - Skyrar's Dark Wolves - Violators - Warband of Subsector Aurelia - Steel Cobras