From 1d4chan
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Founding Unknown
Successors of Imperial Fists
Chapter Master Augus Vanator
Primarch Rogal Dorn
Homeworld Fleet-based
Strength 800 Marines
Specialty Rapid squad level assaults, high-risk targets and objectives, being maximum operator on the battlefield, being tacticool
Allegiance Imperium
Colours Burnished, Blued Grey, with Burnished, Blue Grey Trim
What do you get when you mix SAS tactics, the Spetnaz mentality and an Astartes? An actually competent Space Marine Chapter.

The Retributors are a homebrew Space Marine Chapter. They are most notable for appearing in the Astartes fan film which they were made for.

Their speciality is operations in which they will be operating operationally like the operational operators that they are, that is, they're all about improvisational tactics. Unlike most marines, they are capable of developing battleplans on the fly and working in small fireteams rather than larger squads and companies. In fact, they prefer to work in small independent teams and hit critical/valuable targets to help friendly forces, especially their Impulsor squads, who basically spearhead this strategy. And they all do this with an absolute minimum of dialogue.

They mostly flew under the radar through out Imperial history as they tend to not care for glory, meaning when the job was done they would pack up their stuff and leave while other chapters would break out the champagne. Because of this it's likely they have fought and operated in multiple conflicts and war zones, without their deeds being told to the wider Imperium. They did gain some recognition for their actions during Argosa uprising (which you can go watch on the Astartes youtube channel) as during the clean up operations the entire Chapter disappeared without a trace.

After a while the High Lords declared the chapter lost and when Guilliman returned, a new chapter of Primaris Space Marines were sent to their Fortress-Monastery to replace them. However when the marines arrived the new chapter master and the 1st company found evidence that the original chapter had survived, and was still carrying out operations with out the Imperium knowing. As a result of this evidence the new Chapter master sent the other 9 companies to join a different Imperial fists successor chapter and turned the 1st company into 11th company which he became Captain of. The Retributors 11th Company now holds vigil over the Fortress Monastery and are very secretive about its findings.