I think my brain blocked off the buggiest game I ever experienced. I am sure I had such an experience but I could not recall what game it is at all.
I recall trying out Sonic 2006 at a friends place and I did not even bother purchasing the game because of it, it is not even a finished product in my eyes. Maneater was a very recent one, it is a fun shark game like Jaws Unleashed, but it was definitely bugged on launch day. I had sharks and Orcas fling out of existence, random explosions, and the game crashed the moment I have defeated the final boss, preventing me from seeing the final cutscene of the game with no way for me to redo that scene unless I redo the entire game, making it a very anticlimactic end for a B-movie like shark game. .
You just reminded me of trespasser for some reason, now that was an awful game. Probably the B-movie reference.