Colony 42 was a singleplayer modification for the goldsource engine using Spirit of Half-life 1.5a4. It was to take the player into a space station under attack by alien forces.
- Multiple types of Security Guards - Both Barney and Otis
- Charlie Blanks, a completely new Character
- A new storyline, unrelated to Half-Life
- HD pack compatibility
- Two new weapon skins- Desert eagle and Pipewrench