IBM would fund the entire development of the game, pay royalties for it, and advertise for the game.
Ken and Roberta accepted and started on the project.
For the game, a complete development system called Adventure Game Interpreter was developed.
In the summer of 1984, King's Quest was released to much acclaim, beginning the King's Quest series.
At this point, Roberta convinced Ken to help her develop the game in the evenings after work.