Fu's History
Background
Fu is a demon, and the son of the two main villains in Dragon Ball Online, the artificial being Mira and the evil scientist Towa. He is an artificial being, a unique mutant made from the cells of Mira, Towa, Mechikabura (probably), the Saiyans, as well as all of the other strongest fighters; he was created as the ultimate existence so as to destroy the Time Patrol and revive Demon Realm. His body hides a lot of mysteries, and he was greatly affected by Mira after meeting him. He possesses great power, and inherited a brilliant scientific mind from Towa. Supplemental material for Dragon Ball Online states that he will have a big influence on the world when he grows up.
Upon the defeat of Mechikabura, as the Demon Realm crumbles, Towa creates Fu. Towa - accompanied by Mira - then flees to the edge of a cliff, sending a baby Fu away safely through a rift in space. As he is sucked away by the rift, he bursts into tears, and passes through the rift, left to grow up on his own. At some point, he figures out how to use the strongest sealing spell in history and uses it to gather planets to form the Prison Planet, capturing and recruiting various warriors (including Hearts and his Core Area Warriors) for a massive experiment.
Prison Planet Saga
Fu appears unexpectedly on Beerus' Planet telling those present that he is a friend of Future Trunks. He explains that Trunks has been captured and is currently located on the Prison Planet where resides the most dangerous criminals in the Universe. He urges them to follow after him so they can save him as he teleports away.
In the anime, shortly after when Xeno Goku appears, he attacks Goku thinking him to be in league with Fu. Seeing the two Goku fight, Fu comments on what interesting specimens they are and when Xeno Goku fires a ki blast at him, he effortlessly smacks it aside. When Vegeta asks why he seems to know so much about the planet, Fu tells them all that it is because he is the one who created it.
Fu goes on to explain that he has gathered strong fighters from different planets and timelines and has brought them here to fight each other and notes that Xeno Goku must have allowed himself to get captured so that he could investigate. He also says that Trunks has done the unforgivable by using the Time Machine so has brought him there as punishment and also as a means to draw in Goku and Vegeta as well. Finally he tells them that in order to escape they will need to gather the seven Special Dragon Balls which are held by different prisoners on the planet before he teleports away.
Having returned to his laboratory, he watches as the events unfold. Through a speaker, he warns Goku and Vegeta that they should not let their guard down as Cumber arrives to confront them, saying that his evil Ki snaps the mind of whoever it touches.
Fu continues to spectate on the battle, though he becomes angered when he notices giant cracks in the Prison Planet's barrier. He interrupts Super Saiyan Blue Kaio-ken Goku's battle with Golden Great Ape Cumber to reprimand Cumber, activating his Super Fu state with a single slash of dark ki. Raising a purple blade of energy into the air, he absorbs the Power Ball Cumber used to transform. With another slash, Super Fu cuts Cumber's Great Ape transformation short, effortlessly dodging his attacks and leaving Goku and the gang shocked at his power. Fu then drops out of his own transformation, letting the battle continue as he avoids a blast from Golden Cooler by teleporting back to his laboratory.
Upon returning back to his lab, he finds that it has been destroyed by an unknown assailant, putting Fu into a rage. He heads back to the battlefield to find that the seal surrounding the Prison Planet has been destroyed. Fu spots Xeno Goku and Xeno Vegeta and realizes that they are the ones responsible for having destroyed his lab. Fu acknowledges that his plans have been ruined and he will now punish those responsible, transforming into Super Fu in the process. Xeno Goku and Xeno Vegeta tell him that it is their mission to capture him and they all engage in battle.
Fu appears to gain an advantage over the two Saiyans but the battle is cut short when Cumber shows up again and unleashes a barrage of Ki Blasts. The attack causes a crack to forge in one of the planets above. Noticing this, Fu claims that his objective has been achieved and that "they" will soon appear and make events much more fun. Using his abilities, Fu opens up a portal which he escapes through.
Universal Conflict Saga
On another planet, Fu appears in a laboratory, observing on monitor the battle between Vegeta and Kamioren expressing how much fun he is having and how exciting his experiment has become. Looking at another monitor with a modified Cooler on the screen, he comments that it will soon be his time to make a grand entrance.
Some time later, he watches the battles unfold between the Dragon Team and Core Area Warriors in Universe 7, noting that it is the perfect place for Hearts to gather energy toward the Universe Seed. His attention is then brought to Rags defeat at the hands of Cooler in Universe 3 followed by his battle against Cumber. When Cooler appears to malfunction during the fight and retreats, Fu notes that he overheated but had nevertheless gained useful data anyway.
Later after Hearts has been defeated, at a remote location, Fu thanks Hearts for showing him great results of universal formation. With a smirk on his face, Fu decides it�??s time for his next experiment.
Universe Creation Saga
Still aiming for the creation of a new universe, Fu obtains the remains of the Universe Seed following Perfect Hearts' defeat and uses it to grow the Universe Tree, he plans to use it in combination with Mechikabura's Dogidogi - which holds enough power to create a new universe. Fu is first seen in a new laboratory, observing Goku's fight with Beerus from afar. As Dogidogi flies to his shoulder, he knowingly contemplates if Beerus was looking for Dogidogi (as opposed to Tokitoki, who Beerus mistakes Dogidogi for).
Fu arrives on Earth along with the bird Dogidogi, with Beerus asking if that is the actual "bird of catastrophe" to which Fu confirms that he is. Fu explains his plans to Goku, Beerus and the others and his intention of creating a new universe using the Universe Tree by attaching the energy of all other universes into the tree before disappearing once again through one of his rifts.
At the base of the Universe Tree, Fu, with Towa alongside him, greets greets Bojack, Turles, Super 17, Meta-Cooler and Dr. W and asks if they want to fulfill their dreams in his new upcoming Universe that he is attempting to create. Bojack however is distracted upon seeing the Saiyan Turles and the two begin fighting. Fu intervenes and stops the two, telling them that their target is Goku and his allies who will attempt to stop them and he has given them the chance to exact their revenge.
Shortly after while both Bojack and Turles are fighting Goku and Vegeta on Earth, Fu appears and voices how glad he is that he powered up his two allies. As they continue fighting, Fu has Dogidogi use his ability to freeze Goku and his allies in place before taking the opportunity to capture Tokitoki and then back a swift exit.
After Goku and his comrades arrive at the Universe Tree, Fu appears and welcomes everyone to the Time Rift. He suggests that they wait to see the birth of a new Universe but suddenly, Xeno Goku, Xeno Vegeta, Xeno Trunks and Xeno Pan are forcibly teleported away by Towa. After she claims that all of this is for Fu, which confuses him, she leaves along with Salsa and Putine, leaving only Goku, Vegeta and Fu behind.
Super Saiyan Blue Vegeta charges at Fu though he easily halts his momentum and unleashes some familiar dark Ki over Vegeta that he recognises as being from Cumber. Fu says that he is interested in Cumbers power as he is shown elsewhere unconscious in a tank with his energy being filtered. Goku tries to aid Vegeta but is too late as Vegeta is taken over and becomes Berserk. Fu repeats the process with Goku and the two enraged Saiyans flail wildly at Fu who easily fends them off before purifying them of their Evil Aura.
Fu turns and looks at the tree, saying that it will soon happen and they should watch as one Universe is destroyed and another birthed at the same time. With time running out, Goku and Vegeta fuse into Vegito. Fu fires a blast of Cumbers evil Ki at him but it fails to take Vegito over due to creating a Ki barrier around himself. Vegito transforms into Super Saiyan Blue and prepares to face Fu.
