A video for Gearbox's cancelled Duke Nukem Begins provides us with an idea of what the game might have been.
In 2008, with Duke Nukem Forever in development hell, artist Gregor Punchatz headed up a Gearbox-commissioned project at Dallas, Texas-based production studio Janimation to create an animated vertical slice to show what Duke Nukem Begins was meant to be.
The video shows third-person shooting, with Duke killing various demons using familiar weapons in an urban setting. We also see four-player co-op. There's a big boss fight at the end, with Duke flying around using a jet-pack. Yes, that's Guerrilla Radio by Rage Against the Machine.
"We poured everything we had into making the most awesome cinematic Janimation had ever created," Punchatz said. "But unfortunately, we got word the game was canceled due to the legal issues with Duke Nukem at the time."
In July 2009, Eurogamer reported that development on Duke Nukem Begins had stopped amid a legal dispute between publisher Take-Two and 3D Realms, which had claimed ownership of the Duke IP over Gearbox.
"It crushed us, as this was what we thought could help us compete with bigger players in the game trailer market at the time," Punchatz said.
"Because it is still a piece I am damn proud of, I am releasing it 13 years after its creation. The whole team that worked with me deserves to see this released into the wild.
"I hope this somehow resurrects this version of the game by showing the world how awesome it would have been..."
Gearbox eventually picked up development duties on Duke Nukem Forever, and released the troubled first-person shooter in 2011. Check out Eurogamer's Duke Nukem Forever review to find out how that turned out.
The battle for Duke finally ended in 2015 with Gearbox retaining the rights to the franchise, although Gearbox ended up suing 3D Realms again, this time over breach of contract relating to the rights to the game's music.