After Jason is found half dead in the Evergreen, the Princesses recover him and take him to the underground labs that is secret to the public. They do their best to heal him but he won't snap out of his comatose state. They began to consider if they should bring Twilight and her friends into this to use the Elements of Harmony.
Note - Okay, so obviously, this was written before season 4 so the Elements of Harmony still exist. Also I was heavily inspired by Article 2. This is set during season 3 where Twilight hasn't become a princess YET. The humans are also in the future fallout setting but there is no war, their is a 'PipBoy' spin off though.