Triona is a kind and compassionate young girl who has suffered from loneliness since a very young age. She was accepted by neither Humans nor Fomors. Even if she was not accepted, she still yet cares for them. In G2 & G3, she was accepted by Ruairi and she loves him so.
In G2, she took care of Ruairi after he was injured by Morgant many years ago in Tir Na Nog. After some time caring for Ruairi, she begins to fall for him and wants his affections. At first Ruairi does not respond to her because she is a Fomor. By the middle, Ruairi begins to grow fond of Triona and comes to her aid when she is in danger. In another part, it was revealed she was Morgant's daughter, and is actually a human. In the end, Ruairi wanted to avenge the humans who attacked Triona and killed Rian.
It is revealed in G3 that Triona is the living vessel of the dormant Goddess of Destruction & Chaos: Macha. Cichol attempts to use Lia Fail, the Ancient Wisdom in Baol Dungeon, to awaken Macha within Triona and use her to destroy Erinn. The final mission of G3 is to stop this event, thwarting Macha's resurrection. On her way to the site, Triona is halted by Ruairi where he attempts to talk her out of cooperating with Cichol. Triona accepts her fate and wants to use her transformation to Macha as a means to win Ruairi's heart. Unfortunately, the player thwarts Cichol's plans to resurrect Macha. In the end, she was last seen to walk out of Baol Dungeon with her father. Even now, she still loves Ruairi.