Game-Breaker: X-terminators are meant to be used on a large number of enemies coming in from different directions. Using one shoots out magick missiles in every direction. And that really means in every direction. There are dozens of them in total. As a result, there's no enemy in the game that can withstand your going next to it and launching several x-terminators so that a great portion of the missiles hit the one enemy.
Most Annoying Sound: The level BGM for Catacomb 3-D wouldn't be so bad if not for there being only one such tune in the game (eight seconds long, looped over and over), which is repeated for every stage. Little wonder why the Catacomb Trilogy simply left out background music altogether.