Baku also known as Bucky is the main character of Jibaku-kun (as known Bucky: The Incredible Kid or Bucky: Searching for World 0) series, a creation of Ami Shibata. He is the son of Baku Senior also known as King Bucky, the twelfth G.C. of Doedicos.
When Bucky was young, he and his father, King Bucky are being attacked by Slash as King Bucky fights Slash in an ensuing battle. Slash manages to froze Doedicos which results them being frozen in solid as the young Bucky is later freed from being frozen while his memories were erased and was teleported in the first world of Primas (1st World).
Several years later, Bucky becomes an anti-social guy who treats his college friends as slaves as a college student in Primas. Despite appearing as a cold person, he has a good heart and cares about his friends. His dream is to conquer the world and be the best Great Child. He was later chosen by Spaak, because of his courage and determination in his goals after he saves his friends from a Trouble Monster. He goes out on his journey with Jibac, his spirit, and his friends Pinky and Kai, seeking to become the ruler of the world.
During his journey, he knows many friends and helped many people. In its passage through Tetras (4th World), he met Dartagnan, and helped him face his fears and destroy the monster possessed by the spirit of his father who lived in his own castle. He also helped Ali Babah from Pentas (5th World), which was hit by a curse by the turtle monster until it was broken where she reveals her true gender to them as a young gay. Broke the curse that were in Hexas (6th World) and Novas (9th World) where the trio are facing the brothers, Live and Dead who are working with Hail to deal against them as Trouble Kids. After the brother's standoff with each other Bucky scolds them for being tricked by Hail and both has to reconcile. He defeated the giant Umbrellan with a Powerful Wave and the brothers finally make up each other as siblings.
He also has a standoff between himself and Runmaru who is unable to rescue his sister from an emperor frog monster named Toad Lord in Seteras (7th World) Bucky eventually defeats the Toad Lord with a Powerful Wave and he scolds Runmaru in how to defeat the monster if he is serious enough to fight it. After Funen convinced Runmaru to choose his own path instead of the rules, The Toad Lord transforms into a giagantic toad who is also rampaging their town. Bucky attempts to defeat it by throwing Jibac in explosion but is no effect as its smoke were eaten by the Toad Load. Bucky tries to punch it for the second time but can't even reach it due to its size as he falls on the edge below only to be rescued by Master Funen who grabs his feet with one of his long mole whiskers. Funen manages to defeat the Toad Lord in his gigantic mole-like octopus form with a Tornado Drill and his Supremacy technique. Later, he helps Lucy in Octas (8th World) from dealing against the bandits called the Balboa Gang from swindling her father's ship as their gamble in getting her father's ship. Bucky suggested to make a big sea race to get her father's ship back from them which she manages to win the race.
When Bucky injures his wrists during his travel in Dicas (10th World) after a trouble monster attack where he meets Hayate the tenth G.C of Dicas in the tropical forest. Due to Hail's conspiracy, he manages to turn the animals into trouble monsters which Hayate blames him for the cause. Suddenly, both men discover that the Holy Tree has been corrupted by Slash with his Poison of Awakening which it causes to attack Hayate and Bucky gains the power of the Great Soldier where he shines in a white light to stop its attacks and saves Hayate.
During their travels in Undicos (11th World) where Joan is the commander of the robot army, Bucky and his group got attacked by her robot armies which results him getting severely injured and Kai was taken hostage. He and Pinky are later rescued by Ash a childhood friend of Joan's and a rebel leader of Stray Cats which makes both of them join the rebel group against Joan. After knowing that Joan's actions in her childhood days, Bucky sets out alone to face Joan who is facing her drive monster Doberg who is coruppted by Slash and he manages to deflect her attack using Jibac in tow. But he was knocked down in both of their spirits collided in explosion which he was nearly get punished by Joan before Doberg attacks her. He was later helped by Kai after being freed from taking hostage and the arrival of Master Funen in his human form while disguising his name as Busta and manages to purify Doberg with a Purifier technique. When Joan coldly attempts to kill it, Bucky stops her as she gunpoints at him stating that the trouble monsters are responsible for attacking her house in her childhood. When Ash was corrupted by Slash with the Poison of Awakening turning him into a purple goo-like robot Trouble Monster, he was taught by Busta using the Purifier technique as he succeeds. He was later confronted by Slash who summon a Black dragon monster as he manages to destroy the monster with this technique that he learned. At the time Joan and Kai are fighting the monstrous Ash, Joan tries to attempt to shoot him with her large bazooka but becomes vulnerable due to unable to kill her own friend as Bucky arrives to join the fray which he stops her from shooting and he uses the Purifier technique to heal Ash in his monstrous form reverting back to his human state, unconscious. After Joan regaining her sanity and reunited with Ash, He and Kai discovers Busta was Master Funen after reverting back to his mole-like octopus form which angers Bucky for his actions. Both men are later seen finding Pinky after being rescued by Spaak who is fighting against Slash and he instructs Bucky, Pinky and Kai to go to Doedicos (12th World).
Arriving at Doedicos, they manage to get through his father's castle and meets his father's spirit, King Jibac in his enormous size. After defeating King Jibac who reverted back to his normal size with a teamwork made by Jibac, Bambi and Bakuzan, he reveals to Bucky about his father, King Bucky who is the twelfth G.C. of Doedicos and Bucky was his own son who was freed from being frozen and his memories were erased before teleporting him to the world of Primas after Slash froze the whole island as his father remains being in frozen whom he has a little respect to him. King Jibac also wants him to replace his father as a Great Soldier but he angrily refuses the offer as he considers him as a trash by stepping it to his foot and he kicks the ice where he was freed while he was younger and simply walks away while heading to Needle Tower with Pinky and Kai. Before King Bucky as the G.C. of Doedicos, Hail their recurring enemy is the previous G.C. of Doedicos who resides in Needle Tower as the sole Great Soldier as also mentioned by King Jibac to them.
When Pinky and Kai are fighting against the fake version of Funen and Silva, Bucky is forced to fight the Princess who is possessed by Slash after being awaken from her cryostasis and with the help of her brother, Spaak who removes Slash from posessing his sister with the Prayer of Heaven, Bucky temporarily defeats Slash and rescue the Princess who is now free from Slash's posession. As the Princess and Spaak leave the twelve worlds with his spaceship (Needle Tower), Slash is still alive in his dragon form until he was ultimatelly destroyed by Bucky while wielding the Princess' sword combined with the 12 spirits. After Slash is destroyed, Bucky reunites with fellow Great Children from the twelve worlds and he realizes that he cannot make his dream come true and the license and watch that Spaak gave him previously in the pilot episode as the successor G.C. was actually a dream and his own dream was finally fulfilled.
Bucky appears to have long spiky black hair with brown highlights at the edge of his spikes and large black eyes as he strongly resembles his father, King Bucky.
His primary outfit consists of a red short sleeved leather jacket with a red collar and black linings and black pockets in each side of his jacket. Underneath is a pale yellow long sleeve loose shirt, light purple denim shorts with light violet long baggy pockets in each side of his shorts, white socks and blue and white sneakers. He also wears white gloves.
During Episode 18 while aiding Runmaru in one episode, Bucky wears a black traditional Japanese vest with a dark blue long sleeved traditional kimono, a white tabi and an off-white traditional Japanese geta. He also wears a pale yellow scarf which is tucked into his black vest and maintains wearing his white gloves from his primary outfit.
While siding with Ash and his rebellion group in Episode 21, he wears a white and dark blue military suit with a black high-neck undershirt and white boots. He also dons a brown shoulder length wig where he conceals his black spiky hair until he was knocked unconscious from both spirits explosion during his confrontation with Joan.
Bucky is described as being cold and anti-social who treats his friends as slaves especially to both Pinky and Kai in their travels over the course of the episode but is also a strong and determined guy who fights against Trouble Monsters or trying to confront fellow Great Children who are sided with Hail or dealing their personal conflicts as seen where he found out that Live is working with Hail to deal against them and later he tries to correct Joan's ways while she attempts to kill her drive monster. In later episodes, he is shown to have a good hearted man and is very fond to others as seen when he polishes Jibac while talking to Hayate during Episode 20. He is also shown to be very confident and focused when fighting against Trouble Monsters or purifying people who were inflicted by Slash's Poison of Awakening by clensing them with a Purifier. During Episode 23, Bucky also has a little respect to his father, King Bucky who is currently frozen in solid before being freed from being frozen in the near end of the episode after King Jibac shows it to him at his father's castle at Doedicos.
Bucky's abilities are shown throughout the series as well as he is a very concentrated character when he easily detects his target in order to take them down easily. He also has a high durability as seen in the near end of Episode 16 where he withstands Live's Soundwave Trap despite being ensnared with this ability to knock them down. His powers is a combination of both a Great Child and a Great Soldier. While siding with Spaak against his sister who is possessed by Slash, Bucky glows in a red light during its confrontation.
Powerful Wave: It is Silva's main ability. It is a similar attack on the common explosion of spirits, but with the power to impact many times greater. Visually are several energy spheres with appearance of spirits. This technique has used throughout the series. In the Hero Dub, it was called Power Wave.
Supremacy: It's a technique taught by Master Funen. The goal is to detect the vital point of the enemy as his eyes are glowing in blue when it was used. This ability will take at least ten years to learn, and Bucky learned in a few hours after he was severely injured.
Golden Bladed Sword: It is Bucky's main weapon throughout the series which his G.C. watch enables him to transform into a golden sword-like blade and it was used as his close range weapon. However in Episode 25, The Princess manages to break his sword as it reverts back into his watch.
Purifier: Another technique taught by Master Funen in his human form after Ash being turned into a Trouble Monster by Slash. This ability is to purify the opponent instead of destroying it. This ability is used to heal Ash in Episode 22. However in Episode 25, this technique becomes useless after it does not affect on Spaak' sister, The Princess while in Slash's Possession. This technique is also called Clensing.
Sword Jibak: Sword that proceeds from the mouth of Jibac. Very sturdy, which becomes golden with the energy of Spaak's sister. This ability has used twice which it was used to fight the possessed Spaak's sister but she manages to break its blade during the fight and later Slash in his real form. This technique is also called Jibac Sword.
Pump Great Jibak: Jibak is in giant size and its explosion is much more powerful. Bucky used this attack to defeat Slash first. This ability has used once when the Princess assists them in their second battle against Slash as she uses her powers to increase Jibac's skills and Bucky gains this new technique.
Princess' Sword: It is the Princess' main weapon during Episode 25 and Bucky uses her sword after the Princess and Spaak leave the Twelve worlds to their home planet with their spaceship (Needle Tower) while facing Slash one final time as he uses this weapon combined with the 12 spirits to ultimately destroys him completely in his dragon form. However, the blade of its sword is broken after usage.
- In the Japanese version of the anime, he is voiced by Akira Ishida. In the Filipino Dub, he is voiced by Louie Paraboles.
- Kosuke Ueki the main protagonist of Law of Ueki has a near resemblance to Bucky who had large black eyes and a similar hairstyle as the color of Ueki's hair is green but with fringes.
- Bucky's primary outfit is based of Junta Momonari from the manga and anime, DNA2.
- Bucky's abilities has a total seven abilities the other being Silva who had five abilities.
- In the last part of Episode 11 during the bath scene, Bucky has no shame to himself while giving an advice to Milly about her dreams while he's standing at the back, naked after he gets out of the spring. In the Filipino Dub however, it was blurred due to censorship reasons.
- In the final episode during the final battle against Slash, Bucky learns to wield the Princess' sword after he uses the Jibac sword against Slash. It was revealed when Spaak is wielding the sword when facing Slash in battle.