“I like to joke that [Call of Duty] Zombies was just all heart, and it was probably also no brains,” were some of the words Treyarch Studio Head Mark Lamia used to open his presentation at this year’s D.I.C.E. Summit.

“Because it’s probably a set up for how not to manage a project — certainly how not to manage a major franchise. And when you really think about it, Call of Duty Zombies shouldn’t exist.”

In the rest of his presentation, Lamia told the story of Call of Duty Zombies, Treyarch’s now ultra-popular Zombie survival game mode that was nearly completely scrapped in Call of Duty: World of War. He offers a heart-to-heart, down-to-earth talk about how it nearly “fucked up” the game’s development, but ultimately went on to help the studio find its own identity and continue to build upon its success with Black Ops and Black Ops 2.

His presentation is now available to watch in full on Variety’s official YouTube channel which you can catch above. We recommend checking it out, as it’s a must-see for any Call of Duty fan interested in the how-to of the series’ development.

Treyarch is now preparing to launch this year’s Call of Duty title, which was officially confirmed to be in development last week. Though its official title is still unannounced, Activision says it will be will be “loaded with innovation” and will be the first release for the studio on the franchise’s new three-year development cycle.