Mork
Introduction
Mork is one of the two Ork gods. He is the more cunning but brutal out of the twins while Gork is the more brutal but cunning. What is the difference you may ask? While to put it in a manner in which most non-Orks could even comprehend, Gork is the one that will bash your face into a pulp if you so there look at him (Which represents the Orks blatant manner on full frontal assault) while Mork is the one that will smash your head in while you aren't looking (Which represents the cunningness of some Orks). Essentially both are not to be confused with with each other.
Mork Himself
As mentioned above, Mork is the Ork God for sheer cunning and determination, due to this he may rival Gork, the Emperor and maybe Khorne as one of the most powerful entities within the Warp. In contrast to his twin Gork, Mork often favors and in return is favored by those of an intellectual level, meaning that BigMeks, Flashgitz or any other Orks who actually use their brains for once are often a prime candidate for Mork. Hence, although Gork may be more physically powerful of the two, Mork is arguably more intelligent and wise of the twins.
History
Of what can be determine on what little (If any) history on the Orks, both Gork and Mork came about during a distant time when all of the Ork's psyche started channeling their existence (And unwonted violence) into the Warp, similar to that of the Eldar, however unlike the space elves the Ork's gods often like to get a bit more 'personal' with their subjects i.e. will offer cosmic aid to whoever is chanting their names long enough and if they decide they are worthy enough of their aid; if they are considered worthy then woe to any forces opposing the tsunami of green people. Although they are both idolized upon, the Orks often have no idea who they are directly praying to resulting in much lulz if a Wyrdboy pray for Gork's space foot to crush the enemy only to have Mork turn up instead to psychically make his head explode for mistaking their identity (Not as if they both care anyways).
The only distinction that can be made between the two is that Gork is the more favored of the two gods for the more common greenskins as he is the manifestation of power and might for the Orks, while Mork is more favored towards Orks that possess a sheer level of intellect and cunning such as BigMeks, Gretchins, Flashgitz and other Oddboyz. Whatever is the case, both are rumored to be more powerful then Khorne due to the sheer number of psychic might of the Orks and may actually have the power to snap Khorne like some sissy deamonette.
Although no one has the faintest idea on what these twin gods may truly look like, they can at least be interpreted through the various designs of the BigMek's Stompas and Gargants which are noted to be effigies of the two gods.