JJK Index Fix
Java mod listed for Minecraft 1.20. Downloads from the MC Java Mods app on Android.
Fixes the JujutsuCraft / Sorcery Fight 'Index 23 out of bounds' error which occurs when joining a congested multiplayer server.
⬇ Download on CurseForgeThe author built this one for Minecraft 1.20.1 on Forge. On other versions it may install and then do nothing.
- Usage -
Add the mod to your server's mod list and you're done!
- Description -
Fixes the JujutsuCraft / SorceryFight 'Index 23 out of bounds' error which occurs when joining a server in which players are currently utilising moves/attacks. This mod fixes these issues with the use of mixin injects and replacements.
- What this mod does / how it will effect your experience -
An 'index out of bounds' error occurs when trying to access an element in an array / list / other through an index that does not exist, thus triggering an exception.
This mod fixes the index issue with the use of mixins in order to solve the issue by removing the problematic code.
This fix will allow you to finally log into servers when other users are currently fighting / using moves.
- How to replicate the bug -
1. Boot up Minecraft with Jujutsucraft / Sorcery Fight installed
2. Attempt to join a server in whcih others are using moves / attacks
You will be greeted with an error saying 'Index 23 out of bounds'. This occurs due to code in the latest Jujutsucraft / Sorcery fight sending a packet at a time and in such a way that the client cannot handle process correctly.
- Edition: Minecraft Java
- File type: .jar
- Minecraft version listed: 1.20.1
- How to install: Install the matching mod loader (Forge, Fabric or NeoForge) for your Minecraft version. → Download the .jar. → Put it in the .minecraft/mods folder and launch that loader profile.
- Where to get it: Opens on CurseForge — not every file is mirrored on our own servers.
Install steps are the general flow for this file type — How to install Minecraft Java mods & modpacks walks through it step by step.
- Ships as jjk_fix-1.0.0.jar — drop this file into the mods folder
- Download size: 9 KB
- Download link checked 18 Oct 2026 — working
These come from our own check of the pack file, not from the source page.