The Prim is the primordial chaos that Gan (the spirit of the Dark Tower) originally rose from, spinning the universes from his navel. The six Beams also arose from the Prim. It has receded since the universe has progressed. During its recession many demons of the Prim became stranded on the shores of all the parallel worlds, choking on the air; however, some adapted and survived. Most of these were sexual predators such as Succubi, Incubi and Oracles. Mia and Maerlyn are also entities of the Prim who adapted and survived.
The Crimson King wishes to bring about the destruction of all the worlds and free the people of the Prim once more, ruling eternally over it.
It is noted by the Crimson King that Arthur Eld once mated with one from the Prim, the Crimson Queen, and that he is their son. However he also calls those of the Prim the Great Old Ones meaning the name may be interchangeable with the Old Ones of the Imperium.
The Prim once contained great amounts of magical energy; this energy was used in the construction of Maerlyn's Rainbow.
The Prim also goes by the name of "The Over" by the Manni.