Aku-mura

Aku-mura is an evil, shapeshifting entity that has been born from the Black Virus of Gaia and played the part as the evil guardian of the Mushroom Kingdom and the new-found member of the Galactic Eggman Empire for countless eons.

Appearance
Though he is capable of shifting form into virtually anything he wishes, his standard form is roughly a humanoid being with a black body, a green mouth, and a red beard extending from the bottom of his chin. He also tends to have six horns, four long and two short, extending from his head, and eyebrows made of red, flickering flame. In his standard form, he also tends not to have legs, with his body simply ending at the bottom with robe-like darkness that sometimes manifests as flames, and he also tends to be several stories tall. A deep droning noise is often heard around him when he appears. Demonic Physiology: Aku-mura is a demonic entity which Jack has described as the personification of primordial evil, Aku is one of the most powerful beings in the series, with only a few who are capable of fighting him.
 * Immortality: A significant aspect in the series is that Aku is ageless and immortal. He requires no sustenance, and cannot be harmed by mortal means. Only the power of divine weapons like Jack's sword, or divine entities are capable of doing him harm. He also can bestow agelessness to others, as he demonstrated when he cursed a Nordic Warrior with eternal life to keep him from joining his friends and family in Valhalla.
 * Shape-Shifting: Aku-mura can change into virtually any form he desires, from a giant dragon to a small insect, or even a beautiful woman. He is able to seamlessly change his size, liquefy himself, or stretch and expand his body. He can even replicate into clones of himself to be in numerous places at once, with his mind inhabiting numerous bodies. At one point, he even manifested a second version of himself to act as a psychologist; performing talk-therapy on himself. He typically changes into animal forms during battle, such as a scorpion or an octopus, adapting to the situation. On one occasion, he also transformed into a huge, amorphous mass of darkness that greatly resembled the evil entity he had previously once been/spawned from, and could alter parts of himself at will. He is also capable of transforming into inanimate objects, as he demonstrated as one point by turning into a giant sphere to crush an opposing army.
 * Supernatural Physicality: Aku-mura can alter his physical capabilities to virtually any level he needs or wants due to his magical shape-shifting abilities. He has manifested superhuman strength, speed, endurance, and senses. No parameters or upper limits have been established regarding these capabilities.
 * Regeneration: While Aku-mura is completely resistant to most forms of attack, he is not invulnerable; items such as Jack's sword or magics such as divine energy can damage the substance from which he is made. However, Aku-mura is able to regenerate to a large degree even against attacks such as these. These sorts of assaults tend to create large, burning holes or gashes in him where he is struck, which Aku can close back up with effort. However, his ability to regenerate in these situations is limited. In many of his confrontations with Jack, damage caused by the sword whittles away at his overall mass and ability to regenerate in the short term, until it tends to leave him as a very small animal of some sort, such as a frog or a mouse, at which point further attacks would presumably either seal him away as Jack's father did, or kill him as Jack intends to do. Given time however, he always restores himself without being any worse for wear.
 * Eye Beams: One of Aku-mura's most commonly utilized attacks, this ability tends to manifest as beams of white or red light that typically incinerates the objects it makes contact with. It can be used either as continuous beams of light, or as staccato bolts of energy. He has used this ability in numerous battles with Jack, and he also used it to destroy the majority of his past kingdom. Aku can also harmlessly teleport beings to places of his choosing through this power. The beams can also slice through objects like a plasma torch, or cause them to explode.
 * Remote Viewing: Using mystical forces in his lair, Aku can create images on the walls to view whatever he wishes. He tends to use this ability most often to simply watch Jack travel while stewing in his unhappiness at being unable to kill the samurai.
 * Teleportation: Aku-mura uses this often for quick appearances or escapes, and to appear before those he has business with, such as the Imakandi.
 * Elemental Control: He can magically project and control the elements of the physical world. These abilities include breathing and projecting blasts and streams fire from his body, manipulating the earth itself, conjuring thunderstorms at will, or emitting waves of sonic force. By combining fire breath with his eye lasers, Aku can also project beams of electricity.
 * Telekinesis: He has shown the ability to move, control and manipulate objects through will alone, even from huge distances. while using this ability, his eyes tend to flash white.
 * Necromancy: Aku-mura has been shown to be capable of animating countless dead bodies and bending them to his will.
 * Precognitive Dreams: On one occasion, Aku-mura was shown to be capable of receiving premonitions of his own future through his dreams, which he can then act upon.
 * Possession & Infection: Aku can use small portions of himself to infect others with his evil. The only time this has been seen was when he incidentally spat up a tiny portion of himself at Jack, which, over the course of a day or so, proceeded to possess Jack, giving him the appearance and personality of Aku. On a related note, he can also use portions of himself to power machinery, as he demonstrated by doing so with the Ultra-Robots.
 * Interstellar Travel: Aku-mura is capable of interstellar travel at at least the speed of light.
 * Time Portal Creation: This was the very ability that Aku-mura was a one way portal forward in time and back.
 * Object Materialization: The ability to create objects and materials out of nothing. He once used this ability to conjure treasures in the presence of the Imakandi.
 * Corruption: Using dark magic, Aku-mura can mutate normally harmless beings into monstrous versions of themselves. During his last known encounter with Jack, he used this ability to transform three small rams into monsters to fight Jack. It is also shown that if the corrupted creature dies, the spell will be broken and the creature will transform back to its original form. Aku-mura also uses this power to curse the Well of King Ozric as well as corrupt Jack through his supposed illness. He was also able to infuse this power into techno music to corrupt children in Jack and the Rave.
 * Combat Skills: Despite never having been shown to have trained at all in any form of martial art, Aku-mura is a very skilled practitioner of hand-to-hand combat. Though not any sort of match for Jack, he was at least capable of defending himself reasonably well against Jack during their duel, while limiting himself to human physicality. He is also shown to be a fairly skilled swordsman, as on one occasion where he stole Jack's sword, he was able to force Jack (who was armed with a sword and shield) into a defensive posture during a bout of swordplay. However, it should be noted that on that occasion that Aku-mura was not limited in the scope of the powers he could employ.