Stan was one of the lucky ones to make it out of the Canterlot disaster unscathed, unfortunately for him that means he now has to deliver a treaty to the princess.
Who happens to be one of his most deepest darkest fears.
With the Queen incapacitated, she turns to one of her few subjects who is still in good health to deliver a treaty to the princess, only problem is that the changeling has a phobia for that hatchling eater.
(A sequel to Celestiphobia.) Carl wants Stan to partake in the tradition of getting drunk to celebrate the success of the treaty. He then realizes what a horrible mistake that was.