Deltarune, the multi-chapter sequel to 2015’s indie smash hit Undertale, is currently blowing up on Steam thanks to the release of Chapter 3 and Chapter 4 this morning after years of anticipation.
The game itself has been out in some format since 2018, when creator Toby Fox posted a series of cryptic tweets before dropping an innocuous download entitled “SURVEY PROGRAM.” That download turned out to be the first chapter of a new game, Deltarune, the name of which is an anagram for Undertale. After a cryptic introduction, the player controls a teenager named Kris who, with their school bully Susie, is dropped into a mysterious Dark World and tasked with saving its citizens by a goat-child named Ralsei.
Deltarune’s second chapter manifested in 2021, revealing something like an adventure-of-the-week format where Kris and Susie repeatedly visit the Dark World in each chapter, meet a new villain, defeat them alongside Ralsei, and return home. In total, the game is expected to have at least seven total chapters, and we’ve known three and four were coming today since Fox announced it in April.
Deltarune, like Undertale, is a turn-based RPG with bullet hell mechanics, and features a cast of both new and returning characters from its predecessor. However, its connection to Undertale itself is mysterious — the characters themselves have key differences from their Undertale versions, no one seems aware of the events of Undertale, and yet the game frequently winks and nods to Undertale’s events in a way that players of both will recognize, even if its in-universe cast doesn’t.
While the game itself is beloved for its zany humor, lovable characters, unique combat, and fantastic soundtrack, much of what fuels the nearly-rabid online interest is related to the mystery of what, precisely, Deltarune is, and how it will ultimately connect with or solve some of the latent mysteries of Undertale.
At the time of this writing, Deltarune already has over 100,000 players on Steam and is the 10th most-played game on Valve’s platform. It’s already surpassed the peak Steam player count of the free Deltarune Chapter 1 and 2 demo, despite costing $25. It’s the top-selling game on Steam right now by revenue, ahead of the likes of Counter-Strike 2, Elden Ring: Nightreign, and Dune: Awakening. But its true popularity will be much bigger, given Deltarune is also out on PlayStation 4 and 5, and Xbox Series consoles now, and its Nintendo Switch and Nintendo Switch 2 versions launch tonight at midnight when the Switch 2 officially releases.
Rebekah Valentine is a senior reporter for IGN. You can find her posting on BlueSky @duckvalentine.bsky.social. Got a story tip? Send it to rvalentine@ign.com.
