Kanohi: Tryna, Great Mask of Reanimation
It wasn’t unusual for Makuta to rule their domains with an iron fist, but Raserix took things to an unheard of extreme by turning his city’s government into a theocracy, with him ruling as the Supreme Praetor, the Toa of the city his priests and deacons, and his Toa Hagah his cardinals. In many ways, Raserix embodied the godhood that Teridax aspired to achieve but on a much smaller scale; most of the region were indoctrinated into his religion and infidels were dealt with on a case-by-case basis (re-education worked for most, but those who were more resistant were given harsher punishments).
Suffice to say, Teridax was not happy with what Raserix had done, but also quickly realized that, although Raserix was a fraud, he did have believers, and the last thing Teridax wanted at that point was to go to war with a people who believes you killed their god. The best way to overthrow the Supreme Praetor, he realized, was the same way he would eventually overthrow Mata Nui: from the inside. Teridax collaborated with Makuta Halumu to create Matoran contrarians who would begin planting seeds of doubt into the faithful. Though they were re-educated or otherwise like all who had questioned Raserix’s word before, after a number of millennia, doubt eventually turned to realization and confusion to outrage. Though his cardinals fought back as hard as they could, Raserix was ultimately killed by the fools who fell for his divine lie.