Enerjak

Enerjak is an ancient god of the Mobian Echidnas. He currently possesses Bowser Jr. and sometimes takes control over him whenever Bowser Jr. is in a desperate situation and has plenty of Power Rings.

Appearance
Originally, Enerjak was a Mobian Echidna; however, after becoming a Chaos Demigod, he started to take forms depending on his vessels.

As Bowser Jr., Enerjak possesses a golden armor. The ornate blue-and-gold outfit is somewhat Egyptian in appearance, resembling that of Egyptian pharaohs and gods, the faceplate in particular, and typically consists of a mask covering all but the lower jaw bearing a red gem on the forehead, a chestplate, red skirt, gold adornments on the arms and legs with red clothing between, boots with rounded gold toes, and the Sword of Chaos on his waist.

Past
Originally, Enerjak was a Mobian Echidna. However, at some point in the past, Enerjak started to research Chaos Energy. Eventually, he managed to ascend into the Chaos Force. That way, he managed to become a god. However, he became arrogant. This arrogance lead to the Highests scattering Enerjak across the Chaos Force. It is unknown if The Merger Magikoopa witnessed that event.

Enerjak had various vessels over time, mostly echidnas. It is known that he forged the Sword of Chaos while into one of the vessels.

Bowser Jr's challenges
Eventually, Enerjak possessed Bowser Jr., making him the first Koopa reincarnation of Enerjak.

On one occasion, Error! Sans challenged Bowser Jr. Since Bowser Jr. couldn't beat Error! Sans in his base form, Enerjak used the Power Rings Bowser Jr. collected to take control over Bowser Jr. He managed to defeat Error! Sans, but then he had to return the body to his rightful owner, as Error! Sans warned Bowser Jr. about the Funtime Animatronics.

Personality
Enerjak was originally a benevolent scientist. However, like most of those who his spirit eventually possessed, he became arrogant due to coming into possession of immense power.

Since Bowser Jr. was originally evil, but became good after the Super Genesis Wave, Enerjak also seems to have a heroic demeanor while controlling Bowser Jr's body. However, he still is a hothead and an arrogant, often bragging about himself being "the embodiment of Chaos", meaning that he still has a lot to learn from Bowser Jr. while he's in base form.

Powers and abilities
The abilities of an Enerjak are highly varied, all derived from the use of the Chaos Forceand limited only to the imagination of the vessel. In comparison to most beings, anyone who assumes the mantle of Enerjak is a near omnipotent. Enerjak has been shown to be capable of teleportation, telepathy, mind control, levitation, control over matter and energy at a molecular level, becoming a giant and super strength.

As Bowser Jr., Enerjak has mostly the same abilities Bowser Jr. has in his base form, albeit stronger: master sword-wielding abilities, capability to create things from thin air with the Magitek Paintbrush, fire breathing, genius level intellect, superhuman strength, predicting the enemy moves with the Sword of Chaos etc.

Trivia

 * In Archie, all Enerjak's vessels were echidnas. That makes Bowser Jr. the first non-echidna version of Enerjak.
 * That, however, unless you count Mixedfan8643's version of Hyper Sonic as an Enerjak.
 * Mixedfan8643 says that Hyper Sonic is "a little like a hedgehog version of Enerjak only he was completely good".
 * It may be possible to be the case for Bowser Jr. to be a good Enerjak, since The Merger Magikoopa claims that "whatever good was inside [Bowser Jr.] got purified". Since Bowser Jr. became one with the Chaos Emerald he used for his Genesis Wave, it may be possible for Enerjak to have been turned good by the Super Genesis Wave as well.