On September 4, 2018, the thirteenth season of Supernatural will be released on DVD and Blu-Ray. The thirteenth season set will include the "Scoobynatural" crossover, as well as deleted scenes, a gag reel and audio commentaries for all episodes, including the Scooby crossover. There will also be an exclusive featurette entitled "Mystery Mash-Up: The Making of Scoobynatural." Additionally, the Blu-Ray will feature a bonus digital copy of the all the episodes.
You can pre-order your copy of the 4-disc set on Amazon.