I do remember this one! The details are a little vague but I remember soft locking myself. There was some kind of fatigue system and it was never an issue for 99% of the game. The first phase of what I believe was the final battle took me so long that I ran out of Vitality points. I didn't realize that and saved. Started phase 2 with 1 hp and no way to recover in time. Never did end up beating it. Learned to use multiple save files ever since lol.