Step 1 - Play through the game¶
There isn’t really any missables in I Am Setsuna, so you are free to just play through the game at your own pace. The only thing you might want to concentrate on is working towards the 200 Fluxations trophy, as leaving it at the end will make it a boring grind. You will also want to be careful with the Spritnite-Eaten monsters, as the majority of them are very strong and will likely kick your butt. Basically, if you see an enemy that looks different than the normal ones, avoid it. You also want to not sell the green materials (the ones you get from the sparkles on the map/in areas), as these are used to get recipes.
Step 2 - Beat Game and Sidequests¶
By this point, you have gotten the airship and the World Key, which means you can go around and open up all of those locked chests, which contain some good items and equipment. Just prior to going after the final boss, you will find a portal that will bring you back to the beginning of the final dungeon. It is at this opportunity that the game’s various sidequests will become available. The ones for each character will net you the specific Spritnite trophies and once you finish all of those, you can fight one of the game’s optional bosses.
Step 3 - Cleaning Up¶
Ok, you’ve beaten the main story once and have finished all of the sidequests. The only thing remaining now is to clean up any remaining trophies you have left. This might include those related to Momentum and Fluxation (specifically, the 200 Fluxes), as well as any of the food-related ones if you didn’t get them yet. If you haven’t done so yet, return to the final boss and defeat it without touching any of the four pillars, as this is the final form and is needed for a trophy.