We detected an error in stderr_stream.log about duplicated packages: Modules mixinextras.neoforge and MixinExtras export package com.llamalad7.mixinextras.sugar.ref to module crabbers_delight_expand This error means mods are exporting packages with the same name to the game, while only one can be loaded. Basically, this either means the same mod is present twice, or there is a dependency conflict. You have 2 ways to fix this crash: 1) [RECOMMENDED SOLUTION] Keep only one of the mods listed below, and report the issue to both mod authors. They should relocate it or use jarInJar for their dependencies. 2) [TEMPORARY FIX] This is not recommended: it sometimes works, sometimes doesn't, and can cause unexpected issues. Open the mod as an archive and delete the 'com.llamalad7.mixinextras.sugar.ref' folder in all mods listed below except one. Mods containing the mentioned package: aether-1.20.1-1.5.2-neoforge.jar!/META-INF/jarjar/mixinextras-forge-0.2.0-beta.9.jar!/META-INF/jars/MixinExtras-0.2.0-beta.9.jar aether_protect_your_moa-1.20.1-1.0.0-neoforge.jar!/META-INF/jarjar/mixinextras-forge-0.2.0-beta.9.jar!/META-INF/jars/MixinExtras-0.2.0-beta.9.jar BadOptimizations-2.4.1-1.20.1.jar!/META-INF/jars/fabric-mixinextras-fabric-0.2.2.jar carryon-forge-1.20.1-2.1.2.7.jar!/META-INF/jarjar/mixinextras-forge-0.2.0-beta.6.jar!/META-INF/jars/MixinExtras-0.2.0-beta.6.jar celestial_core-1.5.6.jar!/META-INF/jarjar/mixinextras-forge-0.2.0-beta.8.jar!/META-INF/jars/MixinExtras-0.2.0-beta.8.jar enhanced_enchanting-1.2.2.2-forge-1.20.1.jar!/META-INF/jarjar/mixinextras-neoforge-0.5.0.jar twilightdelight-2.0.17.jar!/META-INF/jarjar/mixinextras-forge-0.2.0-beta.8.jar!/META-INF/jars/MixinExtras-0.2.0-beta.8.jar visuality-forge-2.0.2.jar!/META-INF/jarjar/mixinextras-forge-0.2.0-beta.6.jar!/META-INF/jars/MixinExtras-0.2.0-beta.6.jar