Duke Nukem Forever Is Gold

[Great Rumbler]

3D Realms made a lot of money off of Duke Nukem 3D, Duke related products [including some other games], and licensing their engine. They also had a really small team working through all those years, so the company was probably costing less than a million a year to operate.

The latter really hurt development because games kept getting more complex, yet they never increased the size of the team.