Janemba Character Facts

Janemba is a demon of pure evil and great power created when a teenage ogre, also known as the Saike Demon,[1] who was responsible for watching the Soul Cleansing Machine in Hell slacked off, and the cleanser exploded as a result of the ogre's carelessness. The evil formed around him to create a giant, yellow, and childlike being that turned Hell into his own paradise.
Eventually, Janemba's weaker first form is destroyed by Super Saiyan 3 Vegeta, forcing a transformation into his second state, which enables him to overcome Vegeta.
His power over dimensions is capable of transforming the entire universe into his image, including the Other World. He possesses great matter manipulation powers as well since he was easily able to pick up a club and alter its molecular structure, turning it into a sword. Aside from his power over dimensions and matter, he is also proved to be an accomplished martial artist, taking on both Vegeta and Goku in hand-to-hand combat, and winning.
In both forms, Janemba has a rather unusual weakness: he is physically hurt by insults. Whenever he or any of his constructions are insulted, he or it cracks slightly and shatters like glass. However, it is not enough to be useful against Janemba due to his powers of rapid regeneration, and stuns him only briefly. His constructs, such as the barrier around the Other World station, do not regenerate, but, like Janemba, crack only slightly and must be insulted numerous times before they can be broken. Only Pikkon seems to be aware of this weakness, as he got frustrated and insulted one of Janemba's creations.
The Saike Demon is a tank-boy, who works for King Yemma in Hell, on the Soul Cleansing Machine. This ogre goofs off on the job by listening to heavy metal music on a handheld, and the Soul Cleansing Machine overloads and breaks, covering him in thousands of years of evil energy and mutating him into Janemba.
Janemba is chubby and extremely large. Janemba's intelligence also seems quite limited; the only word he knows how to say is his own name. His attacks involve things such as creating miniature versions of himself and of Goku, creating dimensional portals, and shooting ki blasts from the four holes on his belly. Janemba also seems to be playful and not really trying, much like Majin Buu.
Janemba's Janemba Final Form is much more powerful than his first and is more structured for fighting. This form is able to use a deconstruction/reconstruction teleportation known as the Bunkai Teleport, portals with which he can attack through, stretch his arm at lengths, turning objects into deadly weapons, project his opponents' own Ki Blasts back at them through portals.
He wields a powerful sword capable of shooting unblockable ki out in strikes, though Goku, who arrived to help Vegeta, destroyed this sword. In this more powerful form, Janemba overpowers Vegeta even when he is at Super Saiyan 3. Even after Goku shows up, Janemba is still able to effortlessly overpower the both of them. However, once they successfully fuse to form Gogeta, Janemba is unable to faze them with even his most powerful punches. In a short time, Janemba is defeated effortlessly by Gogeta with the Stardust Breaker, restoring the Saike Demon to his original state.