About Deltarune Fight Simulator

A place to practice your next battle

Deltarune Fight Simulator is an independent fan site for browser-based DELTARUNE and UNDERTALE battles. We bring together playable fan projects, game-specific controls and practical guides so you can choose a fight and learn its patterns. We did not create these games and are not affiliated with Toby Fox or the DELTARUNE and UNDERTALE teams.

Our website is deltarunefightsimulator.com. You can play without creating a site account or purchasing a membership.

What you can find here

The homepage features Battle Simulator V4, with six more battle pages for Jevil, Spamton NEO, Asgore, Queen, Undyne the Undying and Sans. Some projects recreate DELTARUNE encounters; others draw from UNDERTALE. Each is a separate fan-made experience.

• Embedded games that run in your browser, with fullscreen and reload controls.
• Individual control lists, startup instructions and device notes for each project.
• Battle tips and answers to common questions about loading, gameplay and saves.

Most of these games are designed for a keyboard. Check the instructions on the game page before starting, especially if you are playing on a phone or tablet.

Credit to the game creators

The creators below made the playable projects. Our site brings them together and supplies surrounding guides; credit for the games, artwork, music and underlying characters remains with their respective creators and rights holders.

• Deltarune Fight Simulator — Scube3000 · Creator’s project for Deltarune Fight Simulator (opens in a new tab)
• Jevil Fight Simulator — tripoid · Creator’s project for Jevil Fight Simulator (opens in a new tab)
• Spamton NEO Fight Simulator — The_CommanderRS · Creator’s project for Spamton NEO Fight Simulator (opens in a new tab)
• Asgore Fight Simulator — eekeekturtle · Creator’s project for Asgore Fight Simulator (opens in a new tab)
• Queen Fight Simulator — tripoid · Creator’s project for Queen Fight Simulator (opens in a new tab)
• Undyne the Undying Fight Simulator — tripoid · Creator’s project for Undyne the Undying Fight Simulator (opens in a new tab)
• Sans Fight Simulator — Jcw87 · Creator’s project for Sans Fight Simulator (opens in a new tab)

Scratch projects run through TurboWarp. Bad Time Simulator loads from Jcw87’s GitHub Pages build. These services and projects operate independently of this website and may change or become unavailable.

Help us keep the site useful

If a game stops loading, a control is incorrect or a credit needs updating, email support@deltarunefightsimulator.com. Include the page URL and enough detail for us to understand the issue.

Creators and rights holders can use the same address for attribution, embedding or removal requests. See our contact page for the information to include.