While Call Of Duty: Black Ops 4 is available on PlayStation 4, Xbox One, and Microsoft Windows, it does not support cross-platform multiplayer. In other words, if you jump into a multiplayer match on PlayStation 4, you will only face other PlayStation 4 players. The same is true for the Xbox One and Microsoft Windows versions of the game.
If you're looking for a Call Of Duty game that does support cross-platform multiplayer, you're in luck: Call of Duty: Modern Warfare, released in 2019, is the first in the series to offer the functionality. Just like Call Of Duty: Black Ops 4, it is available on PlayStation 4, Xbox One, and Microsoft Windows. You can also mark your calendar for the upcoming Call Of Duty: Black Ops Cold War, which is available now. It will support cross-platform play and extends its player base to the next-generation systems, Xbox Series X/S and PlayStation 5.
Up until Call Of Duty: Modern Warfare, the series had never provided cross-platform multiplayer. It may seem odd in hindsight, but cross-platform multiplayer has proven a bit controversial, especially for the genre of first-person shooters. Some people believe PC players have an unfair advantage over console players due to the use of a keyboard and mouse, which allows for more precise control and movement compared to a controller. However, there's an argument to be made that this negative is far outweighed by the ability to match with friends who are playing on other systems. It expands the pool of players you can match with, too, which may result in less time you'll have to wait for your room to fill up before starting.
In any case, it seems like the series will continue to head in the direction of offering cross-platform multiplayer for new entries. If you really want to avoid cross-platform play, you can typically turn the feature off within the in-game settings or the system settings. That said, doing so will limit you to playing with people using the same system as you.
In better news, both Call Of Duty: Modern Warfare and Call Of Duty: Black Ops Cold War will feature a new prestige system that tracks progression and leveling. This new system is activate for Black Ops Cold War, and it will become available for Modern Warfare players on December 10, kicking off a fresh season for the game. Your progression will count toward your prestige level across both games, so if you don't pick up Black Ops Cold War at launch, you can still make progress by playing Modern Warfare in the meantime.
While Call Of Duty: Black Ops 4 does not offer cross-platform multiplayer, you clearly have options if that's a feature you value. Hopefully, cross-platform play will continue to appear in new entries, along with the option to disable it for those who want to avoid hackers and unfair advantages.
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