The planet of Iritor is the home of many life forms and humans are far from being at the top of the food chain. Many alien races have been trapped in the planets gravity field and have made the strange planet their new home. Most of them haven’t made contact with the colonists and extrapolating from the species already known, humanity should be grateful.

Known life forms

Golems
Orbs
Mutalois
Urks
Jorgalosks

Coming Next:

Grid Essence
...

Golems                                                                                         

Made by the creators, these hulking figures are the guardians of the planet. Crafted by whatever surrounds them, the golem's strength may vary greatly with the substance they are made of. Common to all golems is the ability to channel the Grid’s energy. Since the creators also made the Grid, golems are able to channel its energy at least as adept as any human modulator ever could. 

Orbs_                                                                                       

These floating spheres are about as alien as the world and the Grid itself. Actually they have very much in common with the latter. 
Scientist found out that orbs are most likely some warped form of golems that were produced by errors in the Regulator's respawn subsystems. They don’t have the physical strength of golems but in return the Regulator somehow intermixed the essence of the Grid itself with the orbs. This gives them the highest imaginable degree of control over the Grid making them the world’s most skilled modulators.

Mutalois                                                                                        

These insectoid aliens have been found in various abandoned laboratories where they seem to organize hive-like empires. They are very aggressive and seem to be highly resistant to the toxic and radioactive substances in the labs. As far as the labs go, no one really has a clue as to who built them but it’s pretty sure they are not from the creators but some fellow “guests” on Iritor.

Urks                                                                                        

An apelike species, probably imported to Iritor by one of the alien starships, but grown to huge proportions in Iritor's engineered climate and atmosphere; they may seem dumb and slow when observed from afar but you will notice that intelligence doesn’t matter when an Urk charges you like a bulldozer only faster, much faster. Once they’ve closed in on you they will probably break some of your bones, which rarely matters because they will crush you anyway.

Reports of altered urks, which seem to be even stronger and much harder to kill have sparked fear in most marines, knowing that one of their worst nightmares has become even worse. The masterminds behind the altered urks have not been found yet but are believed to be the same aliens whose labs where overrun by mutalois.

Jorgalosks                                                                                  

The geneticists' view after an initial DNA-analysis, where matching genes with the planets flora were discovered, is that the jorgalosks are native to Iritor, or at least as native as they can be on an artificial planet. Regardless of their heritage, these small reptiles are almost as fast as a bullet and their bites pack enough punch to gnaw through your plast-steel armor anytime, if you are careless enough to let them near you.