While zombies being present in Black Ops 4 was kind of a given, Activision confirmed during today's reveal event that three different zombie maps will launch with the game. Each will feature wildly different themes and have distinct player characters as well as feature bot support for solo players. Along with that, there will be weekly challenges for zombies mode alongside a whole host of customization options. If you feel the game is getting too easy, you can customize the parameters for player health, zombie damage, zombie speed, etc.
via destructoid https://www.destructoid.com/black-ops-4-will-have-three-zombie-maps-at-launch-503459.phtml