Yapool

Yapool appeared in 1972 TV series called Ultraman Ace. Yapool (ヤプール Yapūru) is an evil entity and the main antagonist from Ultraman Ace. He has been defeated many times but proves to be immortal because of his eternal resentment for Ultras. He also tends to avoid death due to his cunning and intelligence, and use of alternate forms and his creations, the Choju, to avoid detection.

Yapool, an ancient creature from another dimension with similarities to Satan and Legion, was an extremely skilled being of many consciousness with a knack for creating biological creations known as Choju. Yapool set his sights for Earth, but the original Five Ultra Brothers sent with their youngest member, Ultraman Ace and Earth's attack team at that time, TAC would came to stop him. Yapool would send many monsters to defeat Ultraman Ace, even seeking alien allies but all failed.

For once, Yapool decided to take the matters on his own by turning himself into Vakishim (バキシム Bakishimu) to attack Earth, first by attacking Minami (the female co-host of Ultraman Ace). While she managed to survive, Vakishim managed to possess (or possibly impersonate) a small boy and used him as a puppet to hide from TAC. As the boy, he set his parents' and his home village on fire in a brutal display. Once TAC found out about the truth, Vakishim escaped from the boy's body and transformed into his true form and fled through his dimensional portal. Vakishim reappeared out from a different portal near TAC's HQ and proceeded to attack, with nothing that TAC's fighter jets could do. Finally, Ultraman Ace arrived to do battle and after a long brutal fight, Ultraman Ace destroyed Vakishim's horn with the Star Beam Cutter and kills Vakishim with the Palm Cutter followed by the Ace Slash. Despite Vakishim's defeat, but Yapool managed to survive in his own.

In episode 23, Yapool took action on his own again, plotting a global scale plan with his two new alias, The Strange Old Man (怪老人 Kai Rōjin) and Giant Yapool (巨大ヤプール Kyodai Yapūru).

One day, Yapool for the first time schemed an invasion on their own hands without using Chojus. They started off by sending an agent of them in disguise as an old man, manipulating children from around the globe by singing a hypnotic music and said the world will end. While Hokuto was patrolling, he saw them but it took Yapool's teleporting ability to catch his attention and rushed to the beach where his kidnapping plot took place. Once arrived, the Strange Old Man transformed his head into that of a gorilla and summoned a snowstorm before he attacked Hokuto with his Fire Breath. Hokuto shot him but that made him fell from a cliff. Fortunately, he survived but heavily injured.

Knowing how far Yapool had gone through TAC decided to attack Yapool in his own domain. Using a special dimensional traveling device TAC sent Hokuto first because he volunteered. However, as the traveling started Yapool began to disrupt it and nearly teleported him into another dimension, but Zoffy arrived and managed to allow him and Minami to become Ultraman Ace. Once Ace was in his dimension Yapool combined themselves and used their anger over Ace and TAC to turn into a single entity, Giant Yapool. The battle between the two giants commenced as Giant Yapool and Ace exchanged beams until he was incapable of going on much further. With Giant Yapool beaten, Ace decided to leave his dimension. The Strange Old Man fainted after his comrades' defeat affect him as well and returning the kidnapped children once and for all. Although Yapol was not killed he would be incapacitated long enough for other aliens to attack Earth while he recovered.

Yapool later schemed his vengeance on Hokuto, who was now the sole host of Ace since Minami had left after countless failure of his plans. He disguised himself as a female dentist and tried to make Hokuto to cause him to go insane by placing a hallucination chip on his teeth while he was given a dental care, causing Verokron II to appear only in front of his eyes everywhere. After Hokuto saw several delusions of Verokron II not seen by anyone else and had taken action himself, he was fired from TAC for his unwarranted assault on what they did not see.

Without Hokuto in TAC anymore Yapool felt satisfied and unleashed the real Verokron II to attack the city. Woman Yapool's tricks were later foiled and was killed by Hokuto himself when he fired his gun at the fiend, as he fainted and was reduced to bubbles. The real Verokron II was eliminated by Ace afterwards while his dental clinic mysteriously disappeared the next day.

Although seemingly dead, Yapool had survived, and then used this alien form (in a juvenile state) as a disguise. He first pretended to be targeted by Yapool in order to get closer to TAC. He later escorted some kids away to safety when Jumbo King attacked the city. Despite talking only in his kind's language but later he told Hokuto via specialized telepathy that he is Yapool in disguise and his true plan was to getting his revenge on TAC, Hokuto/Ace and depriving the children's kindness. Once again, Yapool was killed (seemingly for the last time) by Hokuto before transforming into Ace and fighting Jumbo King. Jumbo King was defeated and Yapool's reign on Earth seemingly ended.

Yapool Man

 * Body Snatch: Yapool is capable of body snatching humans and even his own Choju. While possessing them their abilities and intelligence increase. However, Yapool does not certain some humans by force unless they sell their soul to him.
 * Advanced Technology: Yapool has highly advanced technology such as being capable of turning ordinary animals like pigeons into biological war machines that can go toe to toe against the likes of Ultraman Ace.
 * Black Magic: Aside from technological use, Yapool can even use Black Magic to create choju as seen used on ordinary human to create Cowra and Mazarius, even on Aprasa Fairy to turn her into the monstrous Aprasar.
 * Dimensional Manipulation: Yapool can manipulate dimensions, primarily to transport his Choju to Earth and back. The portals appear to open the sky like an eggshell while doing this.
 * Shapeshifting/Human Disguise: In some operations, Yapool was seen initiated his own human disguise and even masquerade as an Alien Simon. In Ultraman Mebius, his disguise resembles Black Directive.
 * Combine: All of the Yapool can combine together to form Giant Yapool.
 * Immortality: As stated in Ultra Fight Victory, Yapool said himself that he would never die as long as his strong hatred for Ultra Brothers existed. Therefore, once he's defeated, he will return with greater power.

Giant Yapool

 * Blade Hand: Giant Yapool's right arm ends with a large, sharp blade. Effective for bashing and slashing foes.
 * Blade Beam: Giant Yapool can fire a yellow beam from the blade.
 * Blade Blasts: Giant Yapool can emit a powerful energy blast from his bladed left hand. Can cause large explosions and be fired rapidly.
 * Armor: Giant Yapool has armor that allows him to survive attacks like Ultraman Ace's Metallium Ray.
 * Physic Wall Explosion: Giant Yapool can create a wall of explosions as a defensive barrier.
 * Immortality: As stated in Ultra Fight Victory, Yapool said himself that he would never die as long as his strong hatred for Ultra Brothers existed. Therefore, once he's defeated even in any form he resided, he will return with greater power.
 * Telekinesis: Giant Yapool displayed telekinetic powers, allowing him to throw his foes around like rag dolls.
 * Choju Summon: As long as Yapool's energy is sufficient, he will be able to summon Choju. The Choju will usually appear through a giant crack in the sky that would disappear after the Choju exits.