Helryx (DMU)

After the death of Tuyet in the Toa Empire Alternate Dimension, control over the Matoran Universe was taken by a council which consisted of representatives from all the major species of the universe, which was lead by Helryx. She encountered a version of Ynot from a parallel universe on several occasions, who caused several major disasters, such as nearly destroying half the Archives, and causing an avalanche that buried a number of Matoran, some of whom have still not been found.

Apparently she's also D-Klak's girlfriend, which lead Blackout to order The Visitor to capture her. He did so, and she ended up in The Dungeon, where she was convinced that D-Klak was actually on Uterio Di Armechio's side.

After all the inhabitants of the Dungeon were transferred to Teruga Prime (which had been recently taken over by the ZFT), she began to doubt the propaganda which was being fed to her, leading Shockwave to have her brainwashed.

She eventually broke free from this, and joined D-Klak in Ragnarok, where she died fighting alongside the love of her life.

Quotes

 * Ynot: "Helryx, I'm not leaving, but I promise not to destroy anything, I'm just here for some light sparring."

Helryx: "Yeah right, that's what you said LAST TIME! We STILL haven't found all the Matoran that were lost in that avalanche!"

Ynot: "Yeah, yeah, I'll take it to Karzahni, nothing to destroy there."

Helryx: "Fine, but one foot out and the Vahki will be on you faster than you can blink!"