TRIALS of MANA

This set of achievements are all tied to getting to Class 4 with each of the six characters. You can only do this during the post-game section, and the game will specifically walk you through obtaining the Class 4 items. However, you'll need to have made sure you already upgraded your character to Class 3 at this point. For Class 2, you simply need to be Level 18. For Class 3, you need to be Level 38 and have obtained a specific class item by finding a "???" seed type either in a treasure chest inside the dungeons with the Benevedons, or from enemy drops (the Queenebs in Woods of Wandara or the Silver Werewolfs in Chartmoon Tower). Plant that in your magic pot at an Inn and use the associated class item that grows to get to Class 3.

Once you're Class 3 and have obtained the new Class 4 items from the post-game story segments, go back to the statue in the Sanctuary of Mana to upgrade each character to Class 4 for their respective achievement.