Demon King Jackal is the main antagonist of the 1975 manga The Ultraman and also of the 2015 animation The Ultraman: Jackal vs Ultraman.
King Jackal is the king of the Jackals an alien race that held the universe in his hands until Ultraman King banished him and made him pay for his crimes. However, Jackal managed to escape from prison and soon avenged himself by killing Ultraman, he also kills the Ultraman Brothers, ultil they are denied but oppose his government, and he continues to hunt the remaining Ultramans. Then Jackal goes to Earth to enslave the humans, and during the battle, Jackal is soon defeated by when Melos uses Andro Rang, then Jackal pretends for mercy, Melos agrees to spare the tyrant king, but Jackal attacks him from behind and breaks his right arm, and deactivates the armor and launches a powerful beam at Melos to finish him off.
After that, Jackal is proud that the universe is his. However, when Melos soon emerge from the rubble, it irritates Jackal that he attacks him with his beams, but Melos soon counters his beams with the M87 beam that injures Jackal and kills his men, and with Melos' intervention he soon revives the Ultra Brothers, Jackal scoffs at this and attacks him with another beam, but with the combined powers of the Ultra Brothers make Jackal get killed.