Odd has a decent handful of arks, some of which are still ongoing. If I had to frame a general timeline in which the arks occurred it'd go something like:

Odd's birth, arrival in the Petriveil Region, and growing up with help from his dad/extended family

Odd reuniting with Giratina, learning the full scope of his powers/the responsibilities that come with them and him question what his existence is as a result

His high school/early college years where he befriends several other legendary connected people and becoming an agent for an interpol-adjacent organizations

His father dying, Odd entering a little bit of a downward spiral, but able to pick himself up enough in time to see through the climax of a conspiracy that that been developing over the past few years.

Odd after the climax, left alone after his closest friends are either dead, missing or comatose, and as a result some of his remaining extended family work together to sneak him out of Petriveil/cover it up from the organization he's in so he can get away for a while and have some time to reflect.

And his current Arc, manning his shop in Zirca as he sorts through who he is, everything that's happened in his past and what that means for him going forward