Final Fantasy X
Auron's introduction in Final Fantasy X comes after Tidus has fallen to the ground during Sin's attack on the Blitzball stadium. Auron meets him as he is gathering himself together and informs him that he's been waiting.
Shortly after they set out, they are attacked by sins scales and this prompts Auron to give Tidus a sword, a gift from Jecht, he claims. They battle through the waves of enemies and eventually end up near to where Sin is. Auron is seen talking with Sin before he picks Tidus up and tells Tidus that this is his story and it starts here.
Reappearance In LucaFollowing reports that Auron has been sighted in Luca, he does eventually reappear when the Blitzball arena comes under attack from fiends. Following the defeat of the fiends, Auron explains how he defeated Sin with Jecht and Braska 10 years ago, and then went to Zanarkand to watch over Tidus with the purpose of bringing Tidus to Spira. He also informs Tidus that while Jecht is alive, he is also Sin.
Following this, he requests to become Yuna's guardian, as it was something he promised to Braska he would do. He also requests that Tidus be made one of her guardians too, as it was something he had promised to Jecht. Yuna gladly accepts his proposal, although she is quite surprised by the offer.
I Do Not Belong ThereAs the group's travels leads them to the Farplane, Auron refuses to join the rest of them inside as he claims that he does not belong there. When they emerge, Lord Jyscal appears and Yuna sends him. At this moment, Auron collapses, but nobody notices.
After he has recovered, he informs Yuna that this means Lord Jyscal died an unclean death, as he was dead, but still remained outside of the Farplane. Yuna also appears to be hiding something, which Auron notices. However, she denies she has anything, and despite Auron knowing she is lying, she doesn't relent.
Jecht Left This HereWhen they reach Macalania Woods, Auron informs Tidus that there is something he needs to see. After carving a path through the trees, they find themselves in a hidden spring. It is here that he shows Tidus the sphere that Jecht made 10 years ago.
He informs Tidus that Jecht loved him, but he didn't know how to express it. When he made the sphere he had already accepted that there was no way back for him and he made this sphere with the hope that one day he would be able to see it.
Visions of the PastAs the group approach Zanarkand, they start seeing visions of Braska's pilgrimage. The first instance of this displays Auron protesting to Braska about throwing his life away. The second again shows him protesting, because his sacrifice will mean nothing, the cycle will just continue.
The third vision shows Auron's reaction to losing his two close friends. He attacks Yunalesca but is no match for her power. Following this vision, Auron gives a morale boosting speech before he tries to beat Yunalesca again.
In other spheres focused on Auron's past, we also learn about how he could have been a high ranking Yevonite. However, Auron declined the promotion and it eventually went to Wen Kinoc, who went on to become a Maester. Auron also wasn't too keen on the idea of Jecht coming along for the pilgrimage, but he warmed to him after a while.
I Am UnsentFollowing the fight, Auron tells Tidus that he is unsent. After he was defeated by Yunalesca he managed to use his remaining strength to crawl down Mt. Gagazet before his strength evaded him just outside Bevelle. It was here that he found Kimahri and informed him about Yuna shortly before he died.
It is during this passage that Auron shows Tidus another vision of the past, where Jecht is telling Auron that he must find a way to go to Zanarkand and guard Tidus until he is ready to be brought here himself; something which being unsent enabled him to do.
Finally Being SentFollowing the defeat of both Jecht and Yu Yevon, Yuna knows what she must do, but she hesitates. Auron tells her to continue as it's their world now. He's been watching over it for far too long and he has no problems with facing his mortality anymore.
Final Fantasy X-2
Cameo Appearance / Voice Over
Auron's role in Final Fantasy X-2 is extremely minor and he only makes a few brief appearances in flashbacks. The first is a flashback to Zanarkand, while the other shows Auron talking with Gippal.
Auron's voice also makes an appearance during the final battle against Shuyin, where alongside Braska and Jecht, he offers Yuna words of encouragement.