Great game, one of my old favourites, but I just ran into a killer bug which I remembered from years ago (but not well enough to avoid it).
This happens in the 1st Lillen fight on World 3 (Dronicle), although it might be possible to happen in her fight at World 4 (Dissium) as well. For the love of Tiamat, don't disable her (with either Tezolox, Vertalist or Dissium, honestly Tezolox basically can't use Mark in this fight because of it, which is insanely bad and makes her awfully hard to beat without repeating fights or being with a Dissium). Disabling her makes her only able to use Heal which is pretty annoying, but beatable from there, if you've got Numbs or just really high damage output...
But if you would kill her while she's disabled, the game crashes. And not only does it crash, somehow it rolls back your save. A lot. The time from those years ago - note I'm partly assuming here it's a disable glitch and not *just* a Tezolox glitch, as I used Tezolox - Lost then and Tezolox - Elacin now - it rolled me back to the boss fight of World 2.
This time was really special. I'd actually done 1 run through the game with Dronicle - Dissium, then another with Vertalist - Celge, and I was on that Lillen fight with Tezolox - Elacin.
Yeah, I got rolled back all the way to my completed file with Dronicle - Dissium (the first team). I lost an entire save plus the completion record of another one (fwiw), massive yikes.
So yeah, for anyone who might be reading this nowadays, really fun game, but don't disable Lillen (the pink bishop hat eyepatch girl), or she disables your life.
(If you're really worried about this, I'd recommend refreshing the page fairly often, since I'm *kinda* sure the autosave makes a hard record in your cookies when you do that, so you might not get rollbacked more than a fight or two even if you do.)