It was Colonel Traupman who led the rescue force that eventually found Sly Marbo, standing alone and armed only with a knife, covered from head to toe in alien blood. Many Imperial historians recount the horrific details of long, dark nights of torture, in which the Catachan prisoners were dismembered whilst WychesВ and MandrakesВ bathed in the blood of their victims. The small garrison of Guardsmen stationed on the planet were greatly outnumbered by the vast xenos horde, and were eventually overrun. Marbo gained further renown as one of the few survivors who fought during the Dark EldarВ incursion on Galabad. However, tales abound of a lone Guardsman returning two solar weeks later with the head of the Ork Warlord, a single bullet hole clearly visible between the Greenskin's eyes. It is said that he was one of ten brothers who were inducted into the Catachan XII Regiment, and that during fighting against WAAAGH! Urgok on Ryza all were killed. Only Colonel Traupman, Marbo's mentor and original commanding officer, knows the details of his past. Mysterious and aloof, little is known of Marbo's origins and most of what's told remains rumour and speculation. Despite his unparalleled abilities his commanders inwardly feel there is 'something deeply wrong with the boy.' A natural born survivor and a veritable one-man army, he's the ultimate soldier and possesses skills that surpass any of the Imperium's highly-trained operatives. Guardsman Marbo is one of the fearsome 'Catachan Devils,' the closest thing the Jungle Fighters have to the elite Storm Troopers used by other regiments. It is not known whether or not the name 'Sly' is an earned name as per Catachan tradition, or his actual given one. He is known to possess unparalleled military skills, including the ability to handle a Sniper Rifle like a Vindicare Assassin and survival and ambush skills that rival those of any member of the Adeptus Astartes. Sly Marbo, sometimes called the 'One Man Army,' is one of the most decorated members of the Astra Militarum in Imperial history, in this case a revered member of the Catachan Jungle Fighters.

The Catachan Jungle Fighter Sly Marbo sets off an ambush of a T'au armoured detachment

A classified transmission to Segmentum High Command

He disregards Munitorum regulations, he and thank the Emperor that he is on our side.'

Warhammer 40k memes