Rothma

Gahrenn was the toughest Kiryanuian Le-Matoran who lives in the island of Kirya Nui.

Matoran
Rothma exerted as the right hand of the dictatorial Turaga of the island, but he was forced to betray him when the Kiryanuian society turned against his master, and when the Toa Kirya, the main protectors of Kirya Nui made ​​a deal with the League of Six Kingdoms to help them in their quest to rule the Matoran Universe, Rothma was named as the Captian of the Kyrianuian Guard, to create weapons for the League.

The problems for him and all his people came when the Brotherhood of Makuta defeated the League, they attacked the island, and they swept through the island, leaving only 40 Matoran survivors.

The Islanders were forced to surrender, so, after the negotiation, the Makuta allowed them to live in peace. But in return, the Matoran and Toa had to give each and every one of the weapons and technological devices and lock them there forever.

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Trivia

 * Rothma was the only one who didn´t wanted to surrinder to the Makuta, but in time, he was able to accept the surrindering.