DeltaruneChapters 3 and 4 are a wild ride. By now, you’ve likely completed Chapter 3 and maybe even experienced its secret ending. Now, we’re on to Chapter 4, and oh boy, there’s a lot of ground to cover here.
Fortunately, you won’t need to worry about ranking high in goofy minigames or beating impossible top-down dungeon crawlers to find this ending. Instead, we’re going on a scavenger hunt for special musical symbols.
There are major spoilers forDeltaruneChapter 4 below.If you haven’t played through the chapter yet, proceed with caution!
Table of contents
How to find Deltarune Chapter 4’s secret boss
FindingDeltarune’sChapter 4 secret ending and boss requires entering the Dark Sanctuary after the chapter’s introduction and finding a Golden Piano. You’ll needclimbing gearto access this piano and its answers, requiring you to progress through the story until you unlock this tool. Once you have the climbing gear, you’ll need to explore the Dark Sanctuary and search for the Golden Piano’s music sequence to meet the secret boss.
How to solve Deltarune Chapter 4’s Golden Piano puzzle
Solving the Golden Piano’s puzzle requires finding three sets of musical symbols. They’ll appear as sets of arrows, much like the ones you located for other pianos. You can find these arrows in the following locations:
Entering each area and lighting up your surroundings will reveal arrows you play during the Golden Piano’s puzzle. Finding all three of these music sets will give you the exact solution to the Golden Piano’s puzzle, letting you uncover a key item that’ll lead you directly to the secret boss.
First Golden Piano answer location
Here’s a complete step-by-step guide to finding the first set of Golden Piano arrows:
Second Golden Piano answer location
Here are step-by-step directions to finding the next set of Golden Piano arrows:
Third Golden Piano answer location
Last but not least, you’ll find the first sequence inside the Old Man’s library. As you return to his study, head into the library’s left side, going down the west path once you’re in the narrow bookshelf room. You’ll find a massive waterfall here, with a hidden entrance behind it.
Entering this area will lead you down another pitch-black maze, with blue pulsing light helping you navigate the dark. As you approach a wall with a yellow light, activate it to enter another region, repeating the process until you find your final Golden Piano clue.
Deltarune Chapter 4 secret boss location
With all three answers out of the way, you now have the full Golden Piano sequence you can use to discoverDeltarune’sChapter 4 secret ending and boss. Here’s its written version to make things easier to follow:
“Up, dot, up, left, down, dot, right, dot, right, down, left, dot.”
Once you solve the Golden Piano’s puzzle, you’ll watch a doorway appear behind the Old Man. Head back down the bookshelves and traverse through the library until you arrive in the study room. Entering this room will reveal a magical axe that Susie quickly attempts to take, only to realize she can’t grab it just yet.
After a series of bizarre interactions, she, alone, will enter the secret boss fight. Beating the boss will reward you with the Justice Axe for Susie and another Shadow Crystal. For the sake of avoiding some spoilers, I’ll let you see for yourself what this fight entails.
