Deltarune
Released in October 2018 (Chapter 1) and September 2021 (Chapter 2), Deltarune is the follow-up project to Toby Fox’s 2015 cultural phenomenon, Undertale. While it shares DNA with its predecessor—the same quirky humor, bullet-hell combat, and deeply emotional storytelling—Deltarune is not a sequel. It is a parallel story, one that subverts expectations from the very first frame.
Currently released as a free demo (Chapters 1 & 2) with more chapters in development, Deltarune has already proven itself to be more ambitious, mysterious, and mechanically complex than the game that made Toby Fox a legend.
Deltarune is an episodic role-playing game developed by Toby Fox and published by Fox himself. It is a spiritual successor and thematic companion to the 2015 hit Undertale, sharing similar combat mechanics, humor, and emotional depth, but taking place in a separate universe with a different cast and narrative structure. As of 2026, the game has released two free chapters (Chapter 1 & 2), with Chapter 3 fully completed and Chapters 4 & 5 in active development (as of latest updates). The game is notable for subverting player expectations, questioning the nature of choice, and featuring a unique "bullet hell" turn-based combat system.
No Deltarune article is complete without addressing the iceberg of lore hiding beneath the cute surface. Deltarune
The Knight: The main antagonist who creates the Dark Fountains. Who is the Knight? Is it the mysterious figure seen at the end of Chapter 2? Is it a new character? The most popular (and terrifying) theory is that it is Kris themselves. When they rip out the soul at night, are they going to create the next Fountain?
The Roaring: The apocalypse. If too many Fountains are opened, the balance breaks. The Titan's rise. The sky turns to "Roaring." Darkners turn into mindless beasts. Ralsei is terrified of this, which makes his suspicious eagerness to keep the party small and contained feel less like kindness and more like control.
Wing Gaster (The Royal Scientist): Undertale's forgotten character is everywhere in Deltarune. The "Goner Maker" intro? That’s likely Gaster speaking in his iconic cryptic typeface (Entry 17). The sound effects for the save points? Gaster’s theme. The general consensus is that Deltarune is a "world" Gaster created after falling into his CORE in Undertale. We are playtesters in a broken simulation. Released in October 2018 (Chapter 1) and September
As of 2024/2025, Toby Fox is actively developing the next chapters. In his newsletters, he has confirmed:
Based on the Chapter 2 ending, Chapter 3 likely takes place inside Toriel’s living room. After Kris creates a Fountain at the end of Chapter 2, we see Toriel sleeping on the couch. Expect the TV, the cooking utensils, and the dust bunnies to come to life as enemies. And perhaps... we will finally meet the Knight.
If you played Undertale, you can pick up Deltarune instantly. However, the combat system has evolved. Based on the Chapter 2 ending, Chapter 3
The most common mistake a new player makes is expecting another trip to the Underground. Deltarune shares DNA with its predecessor—same quirky humor, similar battle UI, and cameos from familiar faces (Toriel, Sans, Alphys)—but the philosophy is diametrically opposed.
In Deltarune, you are not the protagonist; you are a passenger. You possess a vessel named Kris, forcing them to go on an adventure they may not actually want. This unsettling premise turns the "friendly RPG" genre on its head, suggesting that the real horror isn't the monsters—it is the player holding the controller.