Ork Characters Introduced so far…
All this information was pulled from the website lexicanum and others
Ork
Orks are a warlike, crude, and highly aggressive green-skinned Xenos race. Orks are the dominant subspecies of the Orkoids, which includes the smaller Gretchin and Snotlings. Although their society is entirely primitive and brutal, the Orkoid race is also the most successful species in the whole Galaxy, outnumbering possibly every other race. However, due to their aggressive and warlike nature, this massive race is split into hundreds of tiny empires, warring as much between themselves as against other races. In the purely theoretical event all the Orks were to unite, they would undoubtedly crush all opposition.
Krork
The Krork were a hardy, green-skinned species who, along with the Jokaero, were created by the Old Ones to defend their last of their strongholds, as Denizens of a much more turbulent Warp clustered around them, having been riled by the violence of the War in Heaven. The Krork were the only one of the young races to escape the Nightbringer's fear of death.
The Krork are also remembered by the Eldar Harlequins for having been fearsome foes at the apex of their might, and an un-named Necron Lord from Naogeddon remarked upon their spread throughout the galaxy as being as plentiful as the Humans.
Trazyn keeps a Krork specimen in his collection, with mountainous shoulders. This may be the same creature as the twelve-metre-tall Orkish monstrosity with an exoskeleton and complex internal organs serving as armour far in advance of Imperial battleplate which which Fabius Bile saw within and speculated may have been a Krork.
Gork & Mork
Ork traits and emotions have a reflection in the warp the same as the traits and emotions of Humans and Eldar do. These Ork traits manifest in the form of the strong, belligerent, and indestructible Ork gods Gork and Mork. The difference between the two gods is very subtle: one of them is brutally cunning and the other is cunningly brutal. The Orks often disagree which is which, and they sometimes fight wars over this matter. Both gods are believed to offer help to individual Orks in battle, but in the grand scheme, it doesn't matter which god is worshiped. Generally, Gork is worshiped by the regular boyz as a more direct manifestation of brutal power, while Mork is the God of Oddboyz, especially cunning Orks like Meks and Weirdboys.