Demongo

Demongo, also known as The Soul Collector, was one of Aku's strongest minions and was a soul or essence collector. He was sent after Jack after he managed to stay alive after Aku's constant attempts on his life.

Personality
Demongo is similar to his master Aku as he is completely evil, but is more cowardly than his master. He does not fight his own battles, but summons the essence of mighty warriors to fight for him. Demongo is obsessed with collecting the essences of powerful warriors and beasts to increase his own power. However he likely did have some level of formidable ability, as he most likely had to defeat at least one powerful warrior to begin his collection. He sees Samurai Jack as just another addition to his collection. His voice is quite high-pitched and whenever he says master, he says it like "mast-aa", with the final syllable almost in a whisper.

Synopsis
Little is known about Demongo's origins or past. The creature may actually be some creation of Aku, due to how he held a skull that held his essence after he was ultimately defeated, and does have some minor semblance to Aku, dark seemingly malleable body and a fire motif as well. He was likely Aku's weapon against heroes, as he had an entire army of skilled, but defeated, heroes against his target until they were slain, allowing him to consume their soul and essence and further increase his power.

Demongo manages to survive a little longer than other villains (besides Aku) in the series. After Jack frees the souls entrapped within him they are resurrected as flesh and blood warriors, rendering him weak and powerless. The only power that might remain is his teleportation. When this happened, he was confronted by the now-living warriors and was quickly overwhelmed and killed. His essence was then absorbed by Aku into a glass skull. Demongo (as an essence) begged Aku for forgiveness, but Aku refused and crushed his prison. (Episode XXIII: Jack versus Demongo, The Soul Collector)

Demongo returns in Episode XCVII having somehow survived when he enters the Da Samurai's bar while he explains his story to Ashi. He states that he is searching for the essence of powerful warriors to steal, but comments that there were none at the bar and leaves. (Episode XCVII)

Powers and Abilities

 * Soul Absorption: Demongo's main forte lies in his ability to absorb the souls of defeated warriors to add to his collection that are stored within skulls that are placed on his upper torso. However he has virtually no personal fighting ability of his own.
 * Limitless Spirits: Once Demongo takes control of an essence he can recreate it as a full warrior indefinitely, effectively making his warriors immortal.
 * Teleportation: Demongo is also capable of teleporting from one place to another at astonishing rates.
 * Reanimation Ray: A yellow white flashing ray that can release an essence from inside the skull.
 * Resurrection: When Jack released Demongo's hold on his victim's souls, they were returned alive rather than passing on. This was accidental on Demongo's part. Demongo was shown to be back in the world of the living in Episode XCVll long after the time Aku executed him long ago but it wasn't shown how.