Shamshel

Shamshel, also referred to as the Great Parasite or the Devourer of Sin, is an enormous insectoid-like being originating from somewhere in the Great Dark Beyond. He appears to take on the appearence similar to that of a robed Qiraji prophet of sorts, although he is capable of manifesting electric tentacles anywhere on his body, he is able to sustain his life virtually anywhere, he is capable of flight and interstellar travel as well as entering usually inaccessible areas such as the Twisting Nether and the elemental planes.

Shamshel appears to have some sort of relation to Ramiel, as they seem to have originated from the same place and point in time. Due to Shamshel's ability to access usually restricted areas, there is no alternate Shamshel from a diffirent timeline, as Shamshel is simply capable of accessing these alternate timelines, thus it is uncertain from which one he came from.

Relevant characteristics
Even regarding Shamshel's elusive origins, he is fully capable of speaking fluently in any language after simply examining the speaker without them even talking. Although usually prefering to be silent, when conversing he is quite level-headed and calm.

Shamshel even predates the primordial stage of Azeroth and rivals the power of the Old Gods and the Titans, although unlike them, he seeks neither destruction nor creation, but has a more secretive agenda. He is also not truly capable of dying, considering that when his body is 'destroyed', the land becomes scarred due to his body exploding in any case. When the explosion occurs, Shamshel is transformed into a highly protective, almost indestructable embryo and is usually buried deep beneath the ground. He then waits for his body to regenerate, which can take up from simply hours to even months, before emerging from the ground in his new, almost identical form, mending the scarred land after his ascension.

The reason he is often refered to by such menacing titles is due to the fact that he has inhabited several worlds in the past as he was supposedly searching for 'the lost one', as he says, and all of these worlds have either been destroyed or shattered without recovery, similar to how Outland is now. The fact that he hasn't left a single world in its original state is most likely because he deems the inhabitants of those worlds 'corrupt' and 'impure'.