Karzahni was the legendary ruler of a domain much feared by Matoran in the dim past. According to ancient tales, in the time before the Great Spirit, Matoran labored in darkness. Those Matoran who excelled at their work were sent to Artakha and allowed to work in the light. Those who worked poorly were sent to another place, one ruled by Karzahni, from which they never returned. The name "Karzahni" eventually became a term Matoran used to scare each other, with each new tale about him becoming more and more exaggerated and frightening.
Karzahni was the twisted ruler of the realm also named Karzahni. He was powerful, almost regal, and quite insane. He was unkind and unmerciful. He ruled the realm of Karzahni for more than 100,000 years. He was a huge figure, with battered and twisted armor. His mask looked like four different masks welded together. His armor was black and gold and studded with sharp blades. He had gauntlets which cracked with energy. His eyes were deep and black and gleamed with madness. In one hand he carried a length of burning chain, his preferred weapon. Although he was very strong, he almost never needed to strike an opponent thanks to his power to make others see nightmarish visions of the future. These hypothetical scenarios usually focused on the horrible consequences of a failed attempt to escape, or some other event, in order to crush his victim's hope. Karzahni used this power to sow doubt and hesitation in those who opposed him.
Because of his isolation from the outside world for almost the entire age of the Matoran universe, Karzahni knew very little about anything outside of his realm. He had no knowledge of the existence of Mata Nui, the Brotherhood of Makuta, or Toa until he encountered Jaller and his companions.
Karzahni carried a flaming chain and wore a mask that looked like four masks melded together. He had the power to make an enemy see a vision of an alternate future, normally a nightmarish one.
Karzahni could cause his chains to burst into flame at will, even underwater. He could hurl these chains to ensnare foes and yank them off their feet. He claimed that not even the legendary Manas were able to break his chains. He was emerald-hued. He had keen hearing. He hated Artakha and anything associated with him.
Karzahni did actually intend to repair the Matoran sent to him, but he was poor at doing it. Like many frustrated artists, after a while he started blaming the medium instead of realizing the problem lay within.
Karzahni was in over his head when he was rebuilding Matoran. Instead of admitting this, he covered it up in spite of the despair and destruction that caused. He was self-centered and put his interests above anyone else's. He carried a chain and had a natural ability to show alternate futures.[10, 11]
Karzahni could not shapeshift, but he could rebuild himself.
It would be debatable how much Karzahni's building skills improved.
Karzahni could rebuild himself. It's part of what he did, and it's what he did to the Matoran he sent to Voya Nui.
Karzahni was arrogant and slightly sociopathic. He had a hard time admitting if he was incorrect and was something of a control freak. He had the ability to appear charming and then turn murderous in seconds.
Karzahni did not feel lonely in his realm.
Karzahni was not stronger than a Makuta.
As he was unfamiliar with Toa, Karzahni had no access to Great Masks.
Karzahni didn't destroy his rebuilt Matoran at least in part because it was still his work. He also didn't want to return them to their homes because he knew he did a poor job repairing them. Therefore, he sent the Matoran away so he would never have to think of them again.
Artakha and Karzahni were at the same power level.
Karzahni's ability to make others see alternate futures came from his mask.
Karzahni did not make masks.
Karzahni was one of the top five most powerful beings in the universe revealed by late 2006.
Karzahni was likely Brutaka-sized.
Karzahni was not always insane.
Karzahni likely didn't know where Artakha's realm was.
Karzahni likely wouldn't care if he saw some of his older rebuilt Matoran again unless they posed some threat to him.
Artakha wasn't likely more powerful than Karzahni.
Karzahni thought of Artakha as a colleague.
Mata Nui's health would not have deteriorated if Karzahni died.
Karzahni was less powerful than Makuta both physically and mentally.
Karzahni was most likely the size of a titan.
Artakha and Karzahni were roughly on the same power level.
- Karzahni was one of Greg Farshtey's favorite characters as of the completion of the 2006 novels.
- Karzahni was one of Greg Farshtey's favorite characters to write about by 2006.
- By March 2006, there were no plans for Karzahni to be a set.
- Karzahni was not planned to be a set by August 2006.[37, 38]
- By September 2006, Greg Farshtey was still not sure if Karzahni would appear in 2007.
- In October 2006, Greg Farshtey was asked if there would be a Karzahni set. He replied it wasn't his call to make, it would be decided by the set designers and marketing team in Denmark. He stated if they were planning one for 2007, he was not aware.
- By October 2006, Greg Farshtey knew Teridax and Karzahni were going to battle each other in web content, but didn't know if it was going to be an animation or not.
- Greg Farshtey was still unsure if there would be a Karzahni set by October 2006, even after he had stated the character would battle Teridax in web content.
- In October 2006, Greg Farshtey stated that Karzahni would be seen in two different forms in 2007.
- By late October 2006, Greg Farshtey was aware that a couple Matoran would appear in a store exclusive set in 2007.