Credited names: Gearbox Software

Oldest to newest, including sub-studios. Releases with unknown years appear last.

1. 1999

   • Half-Life: Opposing Force

     Gearbox Software (developer)

2. 2001

   • Half-Life: Blue Shift

     Gearbox Software (developer)

   • Half-Life: Decay

     Gearbox Software (developer)