Canaletto became the Avatar little over 20,000 years ago. When his term ended 10,000 years later and Satis had won, he refused to give up his place. As Satis fought the previous avatar, he called to O for help, as he was not strong enough to destroy him alone. O refused to do this, and thus forced Satis to banish Canaletto rather than destroy him. From his banishment, Canaletto planned his return as avatar for when Satis' term would end. In this Eva Wei was one of his main pawns. 10 years before the events of the Alwas Cycle, he was responsible for the death of Maya Wei during her final race with Spirit. By achieving this, he was able to make Eva his puppet.
His presence is first shown during the Alwas Cycle, in which he orders a Mad Scrub to sabotage the first Whizzing Arrow being piloted by Rick. After Rick's crash, his own investigation led him to the Mad Scrub, and glimpsed the mark of Canaletto, drawn onto the wall in red ink. Upon discovering a relic with the same symbol, he sought the knowledge of a Shaman, finally revealing the great evil. Canaletto promptly erased Rick's memory of their encounter, however, so that he would not interfere with his plans.
Canaletto, shown to be bound in chains, used his magic to observe the races and subtly manipulate events from his prison. It became apparent that the magician Sul was a threat to his plans, as he had the power to alter destiny at will. During one of the races, Canaletto used his influence to pluck Sul from the race itself, confronting him as a projection to offer a deal; to combine their powers to bring an age of purity. Sul refused, attacking him with a magical blast, seemingly killing him. However, Canaletto used his magic to attack Sul, imprisoning him in another dimension.
Molly, upon winning the great race, was summoned by Satis for the enthronement to become the new Avatar. She refused and returned to the Earth Team module, intending to look for her missing friend Prince Aikka. As Satis's power slowly ebbed away, Canaletto was unbound from the cage, consuming the entire of Ōban in shadows. With the last of his energy, Satis destroyed the Pyramid of Power, where the Avatar's powers were stored. However, this didn't stop Canaletto, who released an energy wave upon Satis.
During the last two episodes of the series, he provided a challenge for the Earth Team, Prince Aikka, and O by reviving two golems with his dark magic. A battle ensued, which ended in O sacrificing itself to destroy the two golems.
Upon entry to the Temple of the Heart, Jordan and Prince Aikka protected Molly from Canaletto, but to no avail. Jordan's lasers did nothing to him, and he retaliated, flinging him against a wall and crippling Jordan's leg with his own cannon. When faced with Aikka's magic arrows, he merely deflected them back, causing an explosion which badly damaged the temple and left Aikka unconscious in a pile of rubble.
With no one in the way of his prize, Canaletto reveals to Molly that she was under his influence ever since her mother was killed. Using her pain this to his advantage, he took control of her completely in order to activate the Pyramid of Power. However, the Creators recognized Canaletto and refused to let him become Avatar again, but being mere spirits they could do little to stop him. Canaletto's plan was finally thwarted when Jordan flung himself into the orb, thus becoming the new Avatar. Crying out "NO!", he was consumed by the new Avatar's energy wave and obliterated completely.
Canaletto at first appears to be a being of great evil, but he believes he is doing a sacred mission as he plans to destroy life in the name of universal purity. He is ruthless, manipulative, malevolent, corrupt, and self-righteous, bringing nothing but destruction. He shows no remorse whatsoever for killing Maya, ruining Rick's racing career, or dragging Sul to his doom as part of his goal. He even shows no mercy to the Mad Scrub, the last of his faithful servants.
As demonstrated throughout the series, Canaletto controls dark magic/energy, which may have been developed over the millennia of his imprisonment. Indeed, even without his physical body, he is a match for both Sul and Satis. He also displays similar powers to Sul, in regards to altering destiny and controlling people.
In his physical form, he is very powerful, even more so than as a projection. He shows great magical strength, enough to defeat Satis and Jordan. He seems to be able to control objects in his physical form, including Aikka's arrows and golems.
- Savin Yeatman-Eiffel, the creator of Ōban Star-Racers, revealed that Canaletto's original design was that of a bird (of bad omen.) Even in his final design, he has a head shaped like a raven's, which is symbolized as a bird of bad omen.
- Despite his great power, Canaletto was not strong enough to kill Sul. Instead, he locked Sul into another dimension.
- His motive for wanting to become Avatar was to create a world of purity, but whether that meant only he existed or whether he meant these words are unclear. Satis spoke out against this, saying it was for the good of himself only, which might mean the former.
- It can be safely assumed that Canaletto comes from a species with an incredibly long life span. During his reign as Avatar, he lived for 10,000 years. He was imprisoned for an additional 10,000 years for the duration of Satis's reign as well, making him potentially well over 20,000 years old by the time he was finally able to set his plans in motion.
- In the Halo Universe , the last remaining Precursor has also the same name Canaletto keeps, The Timeless One.
- Despite being the Main antagonist of the series he only appears in 7 episodes in total. 2 in the Alwas Cycle (1 being a cameo appearance) and 5 in the Oban cycle.
- Canaletto is very similar to Amon, from Starcraft 2. Both characters share the same motives of perfecting the Universe by purging it of live in order to recreate it.