It's not 100% canceled, but Call of Duty: Fog of War sure could have been interesting
It was a 3rd person action/adventure game set in Vietnam, but was put on hold/canceled after the whole thing that went on with Infinity Ward and a lot of people leaving Infinity Ward which resulted in Sledgehammer Games getting offered the job to co-develop Modern Warfare 3 alongside Infinity Ward. And after that Sledgehammer went on to create Advanced Warfare.
Via IGN:
Set against a horrific Vietnam War backdrop, Fog of War was conceived as “Call of Duty with the play style of Uncharted,” Sledgehammer’s Michael Condrey told IGN. “It was really taking our passion for Call of Duty with our experience and expertise from Dead Space and bringing that together to offer fans a new Call of Duty way to play.”
Condrey explained that returning to Fog of War is still possible. “In our hearts, there’s probably a place for that game,” he said. “You never want to say in absolute terms that you wouldn’t go back to it.
Previously, Sledgehammer’s Glen Schofield explained that the demo was a 15 minute gameplay slice built in about six months. Condrey explained that the demo “really gave you a great epic opening, some big moments, some compelling gameplay. There was something there we were pretty proud of.”
http://www.ign.com/articles/2014/09/10/sledgehammers-call-of-duty-vietnam-game-was-called-fog-of-war
