Sometimes we want to start a new mission after the player completes the current mission. For that case, we use the <OnGetNextScreen> event:

...
<OnGetNextScreen>
   (switch

      ; After a mission-success debrief, we start a new mission.

      (= aScreenType 'SuccessFollowUp)
         (block (
            (missionObj (msnCreate ...))
            )

            ; If we successfully created the next mission, then
            ; navigate to the mission screen. Otherwise, we return
            ; Nil, which means do nothing.

            (if missionObj
                {
                   nextScreen: &dsRPGMission;
                   nextScreenData: { missionObj:missionObj }
                   }
                )
            )
      )
</OnGetNextScreen>
...