- Demonic Spiders: The Security Helicopters in the first level of The Horror Continues, for once, kill you instantly the moment you happen to be under them.
- Killer App: The first three games were this for the Amiga.
- Porting Disaster: The PC floppy version of Tower Assault omitted a large number of levels and the non-linear gameplay.
- Spiritual Adaptation: The first game greatly influenced Doom. Which kinda says something if you consider that the series would later get its own FPS spin-off.
- Values Dissonance: One of the cheat codes for the original game was "ALIENS ARE FAGGOTS", which caused the aliens to run away from the player. It was openly printed in every magazine that listed the cheat codes. When the game was re-released, the code was changed to the slightly-less-offensive "ALIENS ARE BENDERS".
YMMV / Alien Breed