"When playing a game, the goal is to win, but it is the goal that is important, not the winning" - Dr. Reiner Knizia
In character mode you get an XP every time you complete a quest. If you finish 8 total character quests and then do more quests before the final game, you use arcade mode cards. Do you get XP from these?
The text in the lower left of p. 23 (bottom of the Character Quests box) suggests they are still quests. So does the first sentence of the Arcade Mode Cards box on the right side of the same page. But the second bullet in the Arcade Mode box on p. 29 suggests they aren’t. Also relevant is the fact that the sheets for tracking information only have one XP box per character quest available. None of these, in my opinion, establishes a clear answer.