An interesting conversation started recently on OverClocked ReMix. The thread is about bugs near the end of a game that made them otherwise unbeatable for whatever reason. A lot of people are sharing their individual experiences about bugged save files, but some people have chimed in with actual glitches that abruptly end game play all together. Sephfire, for example, describes a situation where the last boss of Far Cry: Instinct becomes completely invincible and can not be killed. I did some digging and apparently it IS a common problem with the game itself, not an isolated issue.
I know I’ve never run into anything like this, though I did have a similar experience with the beginning of Chrono Cross. Have you ever been trapped at the end of a game with no escape?