What Is Deltarune and How Does It Relate to Undertale?

Deltarune is the official successor to Undertale, set in a parallel world rather than a direct sequel. It features new characters and music alongside returning ones, plus an upgraded battle system, and follows Kris, Susie, and Ralsei on a quest to restore balance between Light and Dark. If you are trying to place Deltarune in relation to Undertale before playing or reading further, the key point is that it shares heritage and some familiar faces but stands as its own story in its own world.

The relationship to Undertale

The Deltarune Wiki describes Deltarune as "an official successor to Undertale, the cult-classic RPG." Two things follow from that wording:

• Successor, not sequel. The game is a parallel world, so events and characters are not simply continued from Undertale.
• Shared elements, new context. It brings back some characters and introduces new ones, with new music and a reworked battle system.

That combination is why Deltarune can feel familiar to Undertale players while still being a separate story.

What the game is about

The central premise, per the wiki, is a quest to "restore balance between Light and Dark." The main party is:

• Kris
• Susie
• Ralsei

The wiki organizes its coverage around this split, with character listings divided into Main characters, Lightners, and Darkners, and location listings that include Hometown, Closet, Dark World, Card Kingdom, Cyber World, TV World, Dark Sanctuaries, and Flower Kingdom.

Release status and chapters

Deltarune had a paid release in 2025 and, as of the wiki's current information, is still in development. The Chapter Select lists up to seven chapters. The known timeline:

The wiki also notes that new events may be announced through the official newsletter, so chapter news is worth checking there rather than assuming a fixed schedule.

Where to go for more detail

The Deltarune Wiki is the most comprehensive encyclopedia on Deltarune, currently maintaining 1,058 articles and 5,061 files, and it is freely editable by anyone. It is available in English plus nine other languages: Español, Français, Italiano, 日本語, Polski, Português do Brasil, Русский, Türkçe, and 中文.

If you want to go deeper, the wiki's main sections cover Characters, Enemies (basic enemies, bosses, and Shadow Crystal bosses), Items (consumables, weapons, armor, and key items), and Locations. For a spoiler-conscious start, the wiki offers a spoiler-free synopsis.