In a suit filed on June 7, 3D Realms alleges its owed more than $2 million in royalty and advance payments Gearbox has yet to fork over in regards to Duke Nukem Forever. For its part, Gearbox won't be paying anyone anything without a fight.

According to Kotaku, 3D Realms' lawsuit claims Gearbox Software is keeping its royalty statements under lock and key, and won't allow the former Duke Nukem studio to see the books. "Gearbox is simply stonewalling here in an improper attempt to conceal information from 3D Realms that it is absolutely entitled to receive," the suit states. 3D Realms adds Gearbox hasn't paid out any revenue from sales of the sequel, though the Borderlands 2 developer contends that money isn't part of the royalty deal.

Gearbox has since fired back at the now-defunct 3D Realms, calling Duke's creators out on more than one occasion. "Everyone wished that 3DR's game was better received by the market for the benefit of gamers and profit to its creators," Gearbox's statement reads. "While 3DR might not wish the reality that the results make clear, 3DR turned out to be the only beneficiary of the deal. Gearbox Software, meanwhile, experienced damage to its credibility and loss of its money. "

Since 3DR seems unable to accept reality and has chosen to become hostile, Gearbox is forced to bring its actual claims of breach of contract against 3DR and is confident Gearbox will prevail. Perhaps the lesson learned here is to never enter a gaming business deal with a person who has had more lawsuits than shipped games."

2013 has not been a great year for Gearbox thus far, with this latest debacle added onto the Aliens: Colonial Marines mess. It will be interesting to see what happens next with this bit of litigation, and we'll be keeping an eye on further developments.