my worst moment was on tales of abyss on the hardest mode. Me and my friend were taking on the spider boss (the area where you get natalia) Since the game was on the hardest mode, all our (my friend was playing Guy, I was natalia to keep people alive) attacks were doing 1 damage each swing. After 3 whole hours of me casting reraise on everyone and trying to keep enough TP to make sure I can heal, and dodging negative gate countless times.... the boss was finally down to 400 HP! We were getting so close but some how we slipped up... me (as natalia still) and my friend (as Guy) were the only ones left alive because I couldn't hit fast enough to keep my TP up. We were both in critical health and with out thinking we crossed paths while it casted negative gate... we both got hit... we both died.... game over...
Then we just mana burned it with Jade since magic only has elemental resistance
and that only took 1 hour lol.
Another moment was on chrono trigger where you fight those two things in that one place (yeah I know very descriptive lol) its those two monsters that when that die that use that Bio move that hurts your team. ( I believe the place was that underwater palace where Zeal is, not the floating one where you fight her later) Well, I killed one but when I killed the other one it's Bio move killed my whole team so I got to see a game over screen where there were no monster left but everyone was dead -_-
those are the only two I can think of...