Every Treyarch-developed Call of Duty game since Call of Duty: World at War has featured the popular Zombies game mode, and that hasn't changed for the recent Call of Duty: Black Ops Cold War either. Call of Duty: Black Ops Cold War features a mostly traditional Zombies experience, though the developers have made some key changes to give the mode a bigger sense of progression as well as add some quality of life enhancements. However, it seems a much more ambitious Zombies mode may be coming to the game at some point down the line.
Twitter user Okami, who has accurately leaked video game news in the past, claims that Call of Duty: Black Ops Cold War will soon be adding an open world Zombies mode called Outbreak. According to Okami, the Call of Duty: Black Ops Cold War Outbreak mode will be "Treyarch style" and will be "co-op," ruling out the possibility that it will be PvP. Okami also added that the mode will take place "on a large scale Fireteam map," though it's unclear if that means one of the existing Fireteam maps or a new one.
It's possible that this mode will be a new version of Fireteam, as Treyarch has always planned on adding new Fireteam game modes to Call of Duty: Black Ops Cold War. This would presumably offer fans a much different experience than Fireteam: Dirty Bomb, though if it is a proper Fireteam mode, then one would imagine that it would have a PvP element, which isn't mentioned anywhere in Okami's tweet.
Okami provides enough specific details about the supposed Call of Duty: Black Ops Cold War Outbreak mode that fans should know soon enough if this leak is accurate or not. If Okami is correct about the Call of Duty: Black Ops Cold War Outbreak game mode, then it will strengthen their credibility as a source for insider information. But if they are wrong about it, then it will be more difficult to believe their future "leaks." Whatever the case may be, hopefully fans find out one way or another sooner rather than later.
As far as Zombies goes, Treyarch just recently added a new Zombies map to Call of Duty: Black Ops Cold War in the form of Firebase Z. The Call of Duty: Black Ops Cold War Firebase Z map is set in Vietnam, with jump pads and other gimmicks to help it stand apart from the launch Zombies map, Die Maschine.
Future Call of Duty: Black Ops Cold War Seasons will add even more Zombies content to the game, so maybe this open world Zombies mode will arrive with Season 2. However, that's just speculation at this time, and fans will need to standby for more information.
Call of Duty: Black Ops Cold War is out now for PC, PS4, PS5, Xbox One, and Xbox Series X.