Deus Ex: Human Revolution developer Eidos Montreal outsourced the game's controversial boss battles to an external studio, it's emerged.
Montreal-based Grip Entertainment has claimed responsibility for the boss fights, which were widely panned by press and gamers alike for being overly difficult and out of sync with the rest of the game.
Grip president Paul Kruszewski admitted in a behind-the-scenes video that he came into the Deus Ex project with no prior experience of the series.
"Full confession: I'm a shooter guy," he said. "I was coming into this not knowing a lot about the Deus Ex world. The guys at Eidos gave us the design, gave us the engine... and we gave them back that experience.
"Balancing that was brutally hard," he added, but many Deus Ex fans may disagree with his claim that Grip's work on the series was a success.
"I've been building technology for 20 years," he said, "and it's one of the cleanest, best pieces of technology I've ever built."
Human Revolution's first DLC add-on The Missing Link is planned for release next month.