Known in his own world as Lord Malshun (the nearest approximation of his real name that human vocal cords can reach), Mr. Munshun is an extradimensional, demonic entity whose native dimension seems to be in a desolate, flame-blasted part of the same Planet that the Territories of "The Talisman" exist in.
In similar fashion to another extradimensional entity known as Tak, Mr. Munshun seems to be unable to exist outside of his Home Dimension and the confines of the transdimensional nexus in the Black House without inhabiting a Host Body; in Mr. Munshun's case, he inhabits the willing bodies of child murderers, and according to Stephen King cosmology he was partially responsible for murder sprees committed in the past of such real world serial killers as Fritz Haarman and Albert Fish, as well as his latest willing host, the (fictional) child-killer Charles Burnside, also known as the Fisherman.
His physical appearance most closely resembles an extremely large, convex head -larger in height than the rest of the length of his entire body -and most notably a single, semi amorphous eye that from time to time momentarily splits into two eyes and then back again. His mouth, nearly covering the entire lower half of his face, is filled with hundreds of razor-sharp, inward pointing teeth.
Mr. Munshun is himself an agent of the Crimson King, and at the King's behest he scours the dimensions looking for children who are Breakers; Munshun allows his human hosts to torture and/or kill most of the rest of the children they capture in any way they see fit (and derives a great deal of pleasure from their suffering in his own right). Many other children throughout the centuries have been put to work at a gigantic mystic machine called the Big Combination, where they work endlessly (in Mr. Munshun's home dimension, where the machine is maintained and powered, time does not progress normally and the children there are effectively ageless).
Powers and abilities
Mr. Munshun does not display any known powers apart from a Host Body, but has the knowledge of several powerful spellwords (words from the Dark Speech) that were said to be able to protect him in times of need, and in the novel he uses one spellword to cause magical slumber and another spellword -unsuccessfully -to attempt to magically freeze a group of rescuers in their tracks.
As part of a Host Body, however, Mr. Munshun imparts the ability of teleportation to the Host Body -at least in the Fisherman's case. The novel does not reveal to the reader if these same powers were made available to any of Mr. Munshun's previous Host Bodies. Mr. Munshun seems to be able to inhabit and uninhabit a given Host Body at will, although he does not seem to be able to reside in more than one host body at a time. In addition, Mr. Munshun, in conjunction with a human host, is able to send powerful illusions to the families of the victims that he's killed, as well as pick their minds to determine those words, phrases, and images about themselves and their lost loved ones that will have the most devastating psychological effect.
Through unknown means, Mr. Munshun can locate a new Host Body when his current one wears down with age or is killed; at or near the time of the Fisherman's death, Mr. Munshun had already detected a new potential host in New York, hundreds of miles away.
Furthermore, as a favored agent of the Crimson King, the King watches over him and warns him of threats to his person, both near and far; it was the Crimson King himself who alerted Burnside/Munshun that Henry Leyden was close to discovering his identity and directed him to Henry's home, where he later succeeded in killing Henry -although Henry, before he died, was able to positively identify Charles Burnside as the town's serial child killer.
Mr. Munshun was utterly destroyed by a single blow from a baseball bat supercharged with the residual energy of the Talisman that still existed within Jack Sawyer.