Balls of Steel is a pinball-based video game released in 1997 for Windows 95. The game was developed by Wildfire Studios, and it was co-published by GT Interactive and Pinball Wizards, a division of 3D Realms.
Appearance in Duke Nukem games
Duke Nukem 3D
Duke Nukem Forever
In Duke Nukem Forever, exceeding a score of 1,000,000 on a pinball machine unlocks the "Balls of Steel" achievement. The "Balls of Steel Edition" is also the name of an early collector's edition of Duke Nukem Forever.
Kill-A-Ton 2015 Collection
Relation to the Duke Nukem franchise
Although closely related to the Duke Nukem franchise, Balls of Steel is not a Duke Nukem game and was not developed by 3D Realms.
For context, Balls of Steel is a pinball game in which the player may play on several pinball machines. Only one of these pinball machines is Duke Nukem-themed, hence it was licensed to use the Duke Nukem IP. This particular pinball machine also features recorded voice acting by Jon St. John, the voice of Duke Nukem. However, the rest of the game is a generic pinball-based video game and bears no resemblance to Duke Nukem.