Now that fans have had ample time to play Deltarune Chapters 1-4, creator Toby Fox is slowly divulging more behind-the-scenes development details. He already revealed his first-ever sketches of Susie, Ralsei, and Noelle (circa 2015) as well as his original Microsoft Kinect rotoscope ideas for what would become Tenna (circa 2016). Now, Fox is posting less edited versions of past concept art and text documents, which feature lines used in Chapters 3 and 4.
Though Fox posted the same concept art in 2018, he purposely omitted specific lines such as “Bottled… water…?”, “He goes to another school!”, and “I hope it makes you worry a little less.” While some lines are crucial to Deltarune’s story, others set up jokes that Fox conceived almost ten years ago. Given that the file name for the concept art is “THE FUN GANG” (a possible name choice for Kris, Susie, Ralsei, and Lancer’s group), it goes to show how far in advance Fox had mapped out certain aspects of Deltarune.
Over on Bluesky, Fox posted one of the first facts he ever wrote about Susie, which is that she rests her chin on your (Kris’s) head. While this has yet to happen in Deltarune, Susie’s height in relation to Kris’s makes this interaction possible. Considering Susie’s free-spirited nature (despite no longer being a bully), fans can definitely see this happening in the future. Expect more early and less edited Deltarune concepts from Fox as more chapters get released.
Deltarune Chapters 1-4 is now available for Nintendo Switch 1 and 2, PC (macOS and Windows), and PlayStation 4 and 5. Chapter 5 is set to be released sometime in 2026.