While ruling over the planet Spherus Magna, the Great Beings began the 'Great Spirit Project,' which involved creating a pair of automatons to explore and gather data from the universe.

Once enough construction was complete on the first robot, named Mata Nui, Artakha and Karzahni were created and given purpose within him. When Heremus observed the brotherly relationship between Artakha and Karzahni, he thought it would be interesting to have them compete in a contest to see who was superior. Heremus had Kanohi create a Kanohi Xanadu, the Legendary Mask of Creation, and used it as a prize for the contest. Artakha would go on to defeat Karzahni and claim the mask for himself.

As a consolation prize, Heremus gave Karzahni a Kanohi Olisi. Both he and Artakha were also given their own island to rule in the Matoran Universe, but while Artakha's island was a haven, Karzahni's was much more desolate. Like Artakha, he would name his island after himself.

While his brother made his island a haven for good Matoran workers, Karzahni chose to take in the bad ones, intending to repair their faults and return them to their homelands. However, his ability to fix the Matoran was not up to par, and he instead completely rebuilt them, but into weaker forms. He then sent them to the Southern Continent to make sure his failures would not be discovered. Because of this, he was reviled as ‘The Transposer’ by the Matoran.

Later, Karzahni would get the idea to create a machine which could extract artifacts of power from the multiverse, and deliver them to him. With the artifacts' power, he could conquer the Matoran Universe and take revenge on Artakha. But when he built this machine, it malfunctioned, causing any object that contained large amounts of power to extracted instead. Before his machine's malfunction destroyed the Matoran Universe, The Master teleported the dimensional rift it created out into space, leading to the Dimensional Relocation of Luna Magna.

The Master then brought Karzahni to his realm, and offered him the chance to become one of his servants. Karzahni accepted, but his interactions with The Master eventually drove him insane, making him useless to The Master. After Karzahni was returned to his island, the Toa Artakha arrived, and confiscated his machine.

Eventually, the Turaga of the Matoran Universe would stop sending Matoran to Karzahni to be repaired, as none ever returned. In response, Karzahni blamed the Matoran for his failures, and trapped and tortured those that remained on his island. The lack of contact with the rest of the universe eventually caused Karzahni to believe the island he ruled was all there was to the universe.

This worldview shattered after six Matoran that would later become the Toa Inika arrived in his realm, and told him of the Great Spirit Mata Nui, who was on the verge of dying. The Matoran managed to escape Karzahni in Toa Canisters, and Karzahni pursued them, believing he would get the chance to take Mata Nui's power for himself once he died.

He followed the Toa Inika to the Pit, where he was mutated by the waters into an even more monstrous form. There, he encountered Toa Lesovikk and Makuta Teridax, and engaged each of them in battle, only to lose to both beings. The Order of Mata Nui captured Karzahni, and imprisoned him on Daxia.

After the Reformation of Spherus Magna, Daxia was teleported to the ocean of Aqua Magna, and Karzahni managed to escape captivity. Due to the effects of the reformation, Karzahni's mutations were undone. However, Karzahni would soon be killed by Velika, a Great Being in disguise, who framed Karzahni's murder on Toa Lesovikk.

Abilities & Tools

Karzahni had the ability of telepathic scanning, which allows him to survey distant areas for anything of interest. He also possessed formidable strength, though he rarely used his might, choosing instead to defeat his opponents with his Kanohi's powers. 

Despite his realm being intended to be a place where broken Matoran could be fixed, Karzahni did not have the skills to repair the Matoran he was presented with. He instead rebuilt the Matoran into weaker forms, and eventually neglected them entirely.

Karzahni wields a small forge hammer, which he uses both as a tool and a weapon. As well as that, he’s armed with a length of chain that is capable of heating up until it bursts into flames.

Karzahni wears a Kanohi Olisi, the Great Mask of Alternate Futures, which was given to him as a consolation prize for loosing the contest for the Mask of Creation to Artakha.

Personality

Karzahni was an insane and completely unpredictable sociopath. He could be friendly and kind one moment, and then go into a murderous rage the next. He ruled his domain through fear and psychological abuse, such as replacing the masks of his Matoran subjects to rob them of their identities.

Karzahni also had a major inferiority complex, and was horribly jealous of his brother, Artakha. Because of this, he tended to constantly rebuild himself, and change the color of his armor.

Trivia