Deltarune: Chapter 1 - How To Fight Bonus Boss Jevil

The first chapter of Deltarune, the sequel / something to Undertale, is finally available for download for free on console. Originally released in secret back in October, 2018, the first chapter of Deltarune was a sudden surprise for the indie darling, Now everyone can share in this demo — which might be revamped whenever the full release comes along.

And there are secrets to discover here. Deltarune: Chapter 1 features a hidden boss encounter you can unlock by solving puzzles and locating hidden keys. It takes a little bit of effort, but the bonus boss is worthwhile for fans looking for more challenge. This guy, Jevil, doesn’t mess around. He’s incredibly tough. If you’re looking for a boss that matches the difficulty of Undertale’s optional “evil” path boss battles, this guy is your man. Here’s how to find him.

How To Fight The Hidden Jevil Boss | Secrets Guide

Jevil is the secret optional boss in Deltarune: Chapter 1 — you’ll find him at the bottom of Card Castle, locked in a cell. You’ll need to enter the room labeled ‘??????’ to talk to him. To actually fight him, you’ll need to collect three broken keys and fix them.

The ‘??????’ room is reached through the 1B / 1F elevator in Card Castle. At the bottom, you’ll find Jevil’s Cell.

To open Jevil’s Cell, you’ll need to repair the key. There are three Broken Keys you need to find first.

Broken Key A: Talk to Seam (the Shopkeeper) — exhaust all dialogue options to discuss Jevil. You’ll get the key after talking about Jevil.
Broken Key B: This key part is accessible from the Forest — you’ll see the chest in the lower-right corner, but it can only be reached through a secret passage. The hidden passage is in the bottom-right, on the middle of the southern edge. Press against the bottom edge to find the passage.
Broken Key C: The last key part is located north of the chess Field path that leads to Card Castle. Go north (above the path) to find a puzzle. You’ll need to input the correct combination of spade / diamond / heart into the puzzle.
- Combination: Diamond, Heart, Club, Spade

Once you have all three Broken Key parts, travel to the Bake Sale in the Forest and talk to Malius the Smith. He’ll repair the key. You can also repair the Broken Cake!

Take the key to Jevil’s Cell in the Card Castle to unlock it, and you’ll face off against Jevil. Just agree to fight — beware, he’s incredibly difficult. His attacks are hard to dodge, and you’ll have to fight him a very, very long time. There are two ways to pacify him — you can wait until Round #30+ and Pacify him while he’s tired, or keep using Pirouette and Hypnosis until you can Pacify him earlier.