Rak'gol
The Rak'gol are a race of space fairing pirate/psychopathic-murder-lizard/insect/cyborg...things. These guys are literally what happens when the Dark Eldar has all their kinkiness and faggotry replaced by badassary and awesomeness with a slight hint of Rip and Tear! But Games Workshop being Games Workshop, for some reason, didn't seem to create a Codex for these guys, the majority of /tg/ was slightly disappointed by this outcome however, and pray that they would one day receive some added fluff and crunch on this Pirate-Cyborg Lizard Insects.
The Rak'gol from what we have learned, are a species of aliens that like to scavenge and loot other things from other aliens, often their would-be hostages are either killed, tortured then horribly killed, or are sent to areas best not talked about...they are the only race whose origins has not been that much explored by, due to their first contact in the out-most reaches of Ultima Segmentum and that trying to negotiate and talk to them often ends with the interrogator being ripped apart and shat upon, because of this the Imperium have trouble difficulty trying to know what the hell these guys are up to. The only time the Imperium actually get a specimen to study is a dead specimen, and the results are often at best, messy...Being described as reptilian with a hint of Insectoid features, they are infamous for their apparent hard-on for cybernetic surgery turning their already deadly natural designs into even more fiercesome individuals.
Fortunately for the Imperium (Or so they say...) the Rak'gol is easily identified by their apparent ram-shackled designs of their starships as well as being the only race whose technology is worse then the Orks. Humorously despite having shitty tech such as piss-poor Stubbers which are already in piss-poor condition and ray-guns which are literally Nuclear power-plants with a mirror-scope like a Laser, they still manage to be a threat to Imperial ships, which is saying a lot for Imperium general tech-incompetence and tech-degration; and where the Imperium should stand in turns of durability. Furthermore the Rak'gol are the only race where the Imperium has classified them as dumber then the Orks, this is mainly because of their apparent lack of any social skills, and instead replaced them with rasping roars and gibberish, how the hell they manage to even build a gun let alone a god damn star ship is beyond anybodies idea (But then again, Blood Ravens...). They are also known to be pants-on-head hideous, even for the Chaos Gods and the Nids. So congratulations to the Imperium, you have met what counts as the mentally retarded and more socially awkward version of the Ork Freebooterz.