Doom creator John Romero has hinted that he could one day create a new game with ex-colleague John Carmack - which would be "fresh and awesome".
Romero hired Carmack as lead designer at Doom developer id in the 1990s - but the pair have since gone their separate ways.
Carmack is currently working on Doom 4 and RAGE for id. Both titles will be published by Bethesda next year.
Romero, meanwhile, is creating MMO titles with new company Gazillion Entertainment.
"I have no doubt that if John and I had decided to make another game it would be fresh and new and awesome," he told US magazine Gamesauce. "We've both grown a lot in the past 14 years and have a lot more experience, not only in game development but also in dealing with people and game teams.
"Many times you hear of musical groups getting back together after decades apart, and when they try and work together again everything explodes and falls apart because of personality issues and hubris. I really don't think that would happen with John and me."
Romero and Carmack are both credited on games including Doom, Wolfenstein 3D, Heretic and Quake.