I've finally gotten Treasure Trove in Lost Odyssey. Now, with my Lv99 squad, I'll boost up the last immortal, and close the game off at 1000/1000.
For those who need help, my last 2 treasures were:
The 3rd Tablet Fragment in the Crimson Forest (solve the boulder puzzle)
Right next to the ice underwater in the northeast corner of the map
EDIT: I have all 1000 Gamerscore (pre-DLC, which I may not pick up)