https://www.polygon.com/2018/5/18/17366980/call-of-duty-black-ops-4-no-single-player-campaign

This year’s Call of Duty will buck tradition and ship without a traditional single-player campaign, developer Treyarch confirmed today. Instead, the focus for Call of Duty: Black Ops 4 will be almost exclusively on competitive multiplayer and cooperative Zombies mode.

While there will be activities for players who want to play Black Ops 4 solo — they can play Zombies mode with AI-controlled bots or take part in single-player challenge missions — the bulk of the game is multiplayer.