You figure it out after the aforementioned events between 12/3 and 12/5 (if you don't do what they ask you to do on 12/3..)
I'm going for the true ending, already in the next dungeon. Without a guide, my setup already has Loki/Seth/Thor/Melchizedek/Surt heh... excluding the ultimate personas from each arcana, I have the best personas in the game.
XI Wiki



