A unique elemental accessory can be stolen from each of the elemental storyline bosses. A couple of the postgame optional bosses (I don’t remember which ones) have unique equipment to steal.
Those are the only missable things in the game, that I know of. There are no sidequests at all, and there is only one story path and one ending.
If you miss any of the missable items, don’t bother restarting the game. You can just breeze through New Game+ with carried-over levels, if you want a perfect item collection.
It’s possible to sell unique equipment, so be careful at shops.
Victar’s Fanfiction Archive: https://www.vicfanfic.com
Featuring “Memories of an Overlord”, a Journey to Kreisia fanfiction novel
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