Ultraman Blu's History
Ultraman Blu is one of the two main Ultra Heroes of Ultraman R/B, and is the younger brother of Ultraman Rosso and older brother of Ultrawoman Grigio. In the past, he used to have a human form of the same name, but the power of Ultraman had been passed onto Isami Minato in the present day. He specializes in close and mid-range combat.
While Rosso, Blu, and Grigio were escaping from the Balsas Gang (バルサス一味, Barusasu Ichimi), they crash land on Planet O-50, near the Crusader's Peak, which Grigio believes is fate. They meet Frau in a hut at the base of the mountain, and she tells them they would need oxygen inhalation devices climb up the mountain. The Balsas Gang appears and takes Frau hostage, but the three siblings beat them. Unfortunately, they unleash Margodon, who they have no chance of beating. They decide to put the only oxygen inhalation device on Frau, not wanting any third party to get hurt because of them, and climb up the Crusader's Peak, but were stuck in a dilemma whether to attack from there or climb down the other side. Suddenly, the Ring of Light appears to them, giving them the Gyros and R/B Crystals, which they use to transform into Ultraman Rosso, Ultraman Blu and Grigio Bone to defeat Margodon, the Balsas Gang and rescue Frau.
They go on more adventures and gather more R/B Crystals, and eventually become recognized by the Interstellar Alliance. However, Grigio cannot understand why she transforms into a monster. They are sent back to Planet Sanja to inspect on Bakubarba, but discover that the House of Bakubarba has become a child trafficking hub. Bakubarba tries to guilt-trip the siblings, saying that after Mr. Largo acquired Planet Dontak, he sold it off to the Interstellar Alliance, who are also profiting off it. Grigio gets fed up and kills Bakubarba after being taunted. The Balsas gang hears about this and unleashes the monster Fearmonger to kill the siblings. The brothers try to fuse the crystals of light and darkness into a new power, but they fail because they do not connect with Grigio's wishes. Eventually, Rosso, Blu and Grigio defeat Fearmonger without making any sacrifices.
The siblings are then dispatched to Planet Gion to help Zarra Tribe. Alien Egon Ciel created the Murderous Robot Weapons Barrigator 1 and 2 to kill everyone there so that he could take the rare metals for himself. The siblings try to convince the people to evacuate, but they do not listen, saying their god will protect them. The boy Verte shows Grigio a book about a legend of a red dragon, who is said to bring destruction. Grigio becomes Grigio Bone to scare everyone away just before Barrigator 1 arrives to fight Ultramen Rosso and Blu. Barrigator 2 suddenly appears before the escaping people, who fight back after seeing Verte step up. Grigio created the Attack crystal from this event through their combined will and became Grigio Regina, who easily defeated Barrigator 2 and Ciel along with it. Grigio is exhausted and turns back into herself, and is taken care of by the Zarra people, who bow to her after she awakens. Rosso and Blu meet up with their sister after defeating Barrigator 1.
The Ring of Light calls the siblings to Urban Planet Nepta to defeat the rampaging Leugocyte, who had its genes tampered with by a certain blue Ultraman. The siblings used their Gyros to turn the gaseous monster into a solid, but their Gyros' output is weak and the monster is stuck in an intermediate form, which destroys the planet. Unable to sit and watch, Blu attacks, ruining the plan. Rosso and Grigio have no choice but to attack as well. Freezing the monster using the Water and Wind crystals, they throw Leugocyte into space but it regains its gaseous form. Grigio Regina is knocked back down into King and then to Bone. Due to their intense battle, a wormhole was opened and they were all sucked into it, and they ended up near the planet Earth, which Leugocyte sought to drain the life energy out of and then destroy.
Rosso and Blu defended Grigio by entering a beam lock with Leugocyte. However, the siblings lost the battle and crashed down towards Earth as a meteor, in a place that became known as Ayaka City, spreading Ray Energy throughout 1300 points of the Earth as a result of the impact. Grigio grieved over the loss of her brothers, who had died and become scattered as R/B Crystals.
Their next great challenge came in the form of Horoboros, who was able to deflect every finisher fired at it, despite now having the power of the Orb Ring NEO. Despite their efforts, Rosso and Blu were outmatched by the monster. Defeated, the Orb Ring NEO was taken from the brothers by Makoto Aizen, who transformed into Orb Dark once again. After Orb Dark's seeming victory against the monster, and Makoto's unleashing of Bezelb, the brothers transform again and destroy the Bezelb and prepared to fight Orb Dark, but were interrupted by the return of Horoboros, who was then evolved into its Bipedal form by Saki Mitsurugi. Horoboros managed to defeat all three Ultras before returning to its R/B Crystal. The next day, Horoboros returned and the brothers faced yet another tough battle, with all their tactics failing. They were on the losing end until Asahi arrived. She cheered them on and, hearing her prayers, the Orb Ring NEO returned itself back to the two Ultraman brothers, who used the Triple Origium Beam to finally defeat Horoboros.
After that, they were faced by a vengeful Cereza, who transformed into Grigio King via Saki's Gyro. The brothers try their best but they are unable to defeat Grigio King, exhausting all of their techniques. As a final resort, they tried to use Ultraman's and Ultraman Belial's Crystals, but to only be rejected by them. The brothers return the next day after a short recovery period, but even with a new strategy, they were unable to defeat Grigio King until Asahi reminded them of their mother's words - that when the two of them are together, they can do anything. With that, they managed to unlock the power of Ultraman's and Belial's Crystals, which allowed them to fuse into a more powerful being known as Ultraman Ruebe, who fought Grigio King and finally destroyed it.
Unable to convince Saki out of her plan to destroy the Earth along with Leugocyte, Katsumi and Isami transform into Rosso and Blu to stop her from going back to Aizen Tech, having transformed into Grigio Regina to do so. Not wanting to kill her, Rosso and Blu were careful not to hurt her too much, though Saki did not reciprocate their sentiments. Unable to do much individually, the brothers fused into Ultraman Ruebe. Surprisingly, even the Ruebe Vortex Buster was ineffective against Grigio Regina and he was defeated. The Crystal of Destruction
After regaining their Gyros from Ushio, the Minato brothers transformed into Rosso and Blu to defend Grigio Regina from being shot by Leugocyte, countering the Genesis Requiem by firing their signature Ultra Beams, though they were overcome. As Leugocyte prepared to fire at them once more, Grigio Regina stepped in the way and was instantly killed before them. Rosso and Blu charge at Leugocyte and transform into Ruebe but they are soon overpowered and split.
Seeing that they were about to be finished off, Mio locked the Gyros and canceled their transformation in the nick of time to dodge the Genesis Requiem. Rosso and Blu reappeared again after the brothers talk to their mother but they were once again beaten and almost finished off, but just as they were hit, they fused into Ruebe and changed the future that Mio saw, giving her faith in her sons and convinced her to stop her plan. Eventually, Ruebe won by destroying Leugocyte using the Shin Vortex Buster.
Blu first appears fighting Bemstar and Gan-Q, alongside Rosso and Ultraman Geed and finished off both Kaiju while saving an imprisoned Pega. When Snake Darkness begin wreacking havoc on Ayaka City, Blu battled it with Geed and Grigio Regina but was easily defeated after a short battle. During the final battle, the Minato brothers become Ruebe and join forces with Geed and Grigio Regina against Snake Darkness. However when Tregear appeared backing up Snake Darkness, he knocked back everyone else and reverted Ruebe into his components, and everyone was easily overpowered even when Ultrawoman Grigio appeared. Refusing to give up, the Minato siblings fused into Ultraman Gruebe through the Makoto Crystal’s power and joined forces with Riku, who transformed into Ultimate Final once more. Eventually, Gruebe destroyed Snake Darkness via the Gruebing Beam and freeing Yukio from the dark influence.
Katsumi and Isami suddenly find themselves transported to the Land of Light in their Ultra forms, performing their handshake while being unaware of what was even going on. They met the 6 Ultra Brothers, who welcomed them to the Inter Galactic Defense Force Headquarters. Taro explains that the Inter Galactic Defense Force sent Zero to protect Ultrawoman Grigio, who was being targeted by Ultra Dark-Killer, who Taro once defeated. He says that contact with Zero was lost, so they had guessed that Grigio had been kidnapped. Hearing this, the Minato brothers immediately fly off to search for their sister, without giving a chance for Taro to explain further. Because of this, Taro had to send an Ultra Sign to Ultraman Ribut to help them. Rosso and Blu were attacked by Etelgar and fell down to Planet Penol They try to fight him, but his armor is too tough. Just as Etelgar was about to hit them with an energy ball, Ribut appears and defends them with his Blocker Effect. Ribut puts Etelgar in his Strong Net so that the three of them can escape and regroup with the other New Generation Heroes at the Land of Light. When everyone was gathered, they had a group talk to discuss what had happened to them.
Ultra Dark-Killer uses a projection to inform the New Generation Heroes that Ultraman Zero and Ultrawoman Grigio are being held in the Dark-Killer Zone on Planet Tenebris, and to come and face him if they want to rescue their comrades. Upon arriving, Rosso and Blu face off against Ultra Dark-Killer in the Dark-Killer Zone, but are unable to defeat him. The situation is made worse by Dark-Killer creating Ultraman Zero Darkness from the light absorbed from Zero. Grigio heals her brothers, who fuse into Ultraman Ruebe, who defeats both Zero Darkness and Ultra Dark-Killer. The Ultras regroup and transform into their strongest forms to battle a gigantic Ultra Dark-Killer, who had been revived by Ultraman Tregear, with Rosso, Blu, and Grigio fusing into Ultraman Gruebe. The New Generation Heroes and Zero regroup after Ginga finishes off Dark-Killer with the New Generation Dynamite, but were confronted by Ultraman Tregear, who admits he was the mastermind behind these events. The New Generation Heroes decide to go after Tregear.
After Tregear was defeated by Taiga, a part of Grimdo escaped from his body. The New Generation Heroes tracked down Grimdo in space and sealed it away in a crystal, at the cost of their Ultraman powers. In their human forms they descended to Earth to protect Hiroyuki Kudo from the approaching Grimdo. When Grimdo broke out of its seal, Hiroyuki returned the power of Rosso and Blu to their owners via the Rosso-let and Blu-let respectively, but Taiga, Rosso and Blu were still beaten by Grimdo despite their efforts. They were saved by Taro, but were defeated by him as well once he was possessed by Grimdo. Once the other New Generation Heroes regain their powers, they face off against Tregear, the Grimdo-possessed Taro and Tregear's monsters, with Rosso and Blu fighting against Gorothunder. After their opponents receive power ups from Grimdo, Rosso and Blu fuse with Grigio into Ultraman Gruebe to finish off Gorothunder. Initially being trounced by Grimdo after it had absorbed Tregear, the New Generation Heroes fused with Taiga into Ultraman Reiga and defeat Grimdo. The New Generation Heroes give their parting words to the Tri-Squad and Hiroyuki and return to their home worlds.
Following Tregear's defeat, the New Generation Heroes were dispatched across the universe to track down the Devil Splinter|Devil Splinters, the fragmented remains of Ultraman Belial, which could be used for nefarious purposes in the wrong hands. In their hunt for them, Orb, Rosso and Blu arrived on Planet Liquitor in the nick of time to save their fellow O-50 Ultra Fuma from Gina Spectre. Despite their efforts, Gina proved to much for all of them, escaping with a Devil Splinter in hand.
The New Generation Heroes regroup in the Monster Graveyard, where Absolute Tartarus, Alien Bat, Reibatos, Ultrawoman Grigio Darkness and Gina Spectre were attacking Ultrawoman Grigio, Ultraman Zearth, Ultraman Nice and Ultraman Boy to take the Devil Splinter they found there. Ginga and Victory fuse into Ginga Victory while Rosso and Blu fuse into Ruebe to fight Tartarus. However, Tartarus uses the gathered Devil Splinters to empower Reibatos, who recreates the Giga Battlenizer, and fuses Gina with the souls of her brothers to create Gua Spectre before he dies of an overdose. Gua Spectre's new perfect form proved to be too powerful, forcing the New Generation Heroes to fuse into Ultraman Reiga, who easily defeats Gua before defusing into his components. Just after the battle, Geed and Taiga are struck by Belial and Tregear who retreat shortly after, stealing the Beliarok from Z in the process.
