Mjolnir is a hammer that previously belonged to Ultra Magnus, but Jazzimus would eventually kill his rival. Jazzimus named it after Thor's hammer, but it is unknown what Ultra had called it. Jazzimus would wield the warhammer again after Elyoria and Codebind.
Other Universes:[]
It is unknown if other Jazz's have Mjolnirs, but when Savior visited other realms and universes, he brought it along.
Concede was very jealous..
It is known that the Communist Jazz didn't have one, but he already had a Red Energon hammer and sickle. So..
Schism probably has one.
Behind the Scenes:[]
Make jokes.