Iris crashes when joining any world

[PoohBear02]

Minecraft Version

Minecraft 26.1.1

Iris Version

iris-fabric-1.10.9+mc26.1.1

Sodium Version

sodium-fabric-0.8.9+mc26.1.1

Operating System

Macbook Pro (M3)

What is your GPU?

No idea, i got a basic macbook Pro M3 without any expansions on GPU

Java Version

Java 18 (i think?? I have no idea tbh)

Reproduction Steps

1. I've got Fabric installed for 26.1.1, sodium, iris, got my shaders, etc...
2. In the launcher I go to Java edition, check if my game is set on fabric 26.1.1 and open the game.
3. Minecraft opens up, i can see and navigate through the menu.
4. I open a world and then the game crashes.

I tried the following things without success:

• disable shaders before joining a world
• enable shaders before joining a world
• try joining singleplayer- and multiplayer worlds

Without Iris (only sodium) my game works just fine. I can join any world without any problems.

Crash Report file and latest.log

---- Minecraft Crash Report ----
// Quite honestly, I wouldn't worry myself about that.

Time: 2026-04-10 12:58:46
Description: Unexpected error

java.lang.RuntimeException: Mixin transformation of net.irisshaders.iris.pathways.HandRenderer failed
	at net.fabricmc.loader.impl.launch.knot.KnotClassDelegate.getPostMixinClassByteArray(KnotClassDelegate.java:440)
	at net.fabricmc.loader.impl.launch.knot.KnotClassDelegate.tryLoadClass(KnotClassDelegate.java:336)
	at net.fabricmc.loader.impl.launch.knot.KnotClassDelegate.loadClass(KnotClassDelegate.java:231)
	at net.fabricmc.loader.impl.launch.knot.KnotClassLoader.loadClass(KnotClassLoader.java:119)
	at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:490)
	at knot//net.minecraft.client.renderer.LevelRenderer.handler$caj000$iris$beginTranslucents(LevelRenderer.java:6308)
	at knot//net.minecraft.client.renderer.LevelRenderer.lambda$addMainPass$0(LevelRenderer.java:708)
	at knot//com.mojang.blaze3d.framegraph.FrameGraphBuilder.execute(FrameGraphBuilder.java:67)
	at knot//net.minecraft.client.renderer.LevelRenderer.renderLevel(LevelRenderer.java:556)
	at knot//net.minecraft.client.renderer.GameRenderer.mixinextras$bridge$renderLevel$115(GameRenderer.java)
	at knot//net.minecraft.client.renderer.GameRenderer.wrapOperation$cba000$iris$renderLevel(GameRenderer.java:6529)
	at knot//net.minecraft.client.renderer.GameRenderer.wrapOperation$cba000$iris$renderLevel$mixinextras$bridge$93(GameRenderer.java)
	at knot//net.minecraft.client.renderer.GameRenderer.renderLevel(GameRenderer.java:730)
	at knot//net.minecraft.client.renderer.GameRenderer.render(GameRenderer.java:443)
	at knot//net.minecraft.client.Minecraft.renderFrame(Minecraft.java:1433)
	at knot//net.minecraft.client.Minecraft.runTick(Minecraft.java:1378)
	at knot//net.minecraft.client.Minecraft.run(Minecraft.java:991)
	at knot//net.minecraft.client.main.Main.main(Main.java:248)
	at net.fabricmc.loader.impl.game.minecraft.MinecraftGameProvider.launch(MinecraftGameProvider.java:514)
	at net.fabricmc.loader.impl.launch.knot.Knot.launch(Knot.java:72)
	at net.fabricmc.loader.impl.launch.knot.KnotClient.main(KnotClient.java:23)
Caused by: org.spongepowered.asm.mixin.transformer.throwables.MixinTransformerError: An unexpected critical error was encountered
	at org.spongepowered.asm.mixin.transformer.MixinProcessor.applyMixins(MixinProcessor.java:381)
	at org.spongepowered.asm.mixin.transformer.MixinTransformer.transformClass(MixinTransformer.java:237)
	at org.spongepowered.asm.mixin.transformer.MixinTransformer.transformClassBytes(MixinTransformer.java:202)
	at net.fabricmc.loader.impl.launch.knot.KnotClassDelegate.getPostMixinClassByteArray(KnotClassDelegate.java:435)
	... 20 more
Caused by: org.spongepowered.asm.mixin.throwables.MixinApplyError: Mixin [flashback.mixins.json:compat.iris.MixinIrisHandRenderer from mod flashback] from phase [DEFAULT] in config [flashback.mixins.json] FAILED during APPLY
	at org.spongepowered.asm.mixin.transformer.MixinProcessor.handleMixinError(MixinProcessor.java:686)
	at org.spongepowered.asm.mixin.transformer.MixinProcessor.handleMixinApplyError(MixinProcessor.java:637)
	at org.spongepowered.asm.mixin.transformer.MixinProcessor.applyMixins(MixinProcessor.java:368)
	... 23 more
Caused by: org.spongepowered.asm.mixin.transformer.throwables.InvalidMixinException: @Shadow method isHandTranslucent in flashback.mixins.json:compat.iris.MixinIrisHandRenderer from mod flashback was not located in the target class net.irisshaders.iris.pathways.HandRenderer. No refMap loaded.
	at org.spongepowered.asm.mixin.transformer.MixinPreProcessorStandard.attachSpecialMethod(MixinPreProcessorStandard.java:436)
	at org.spongepowered.asm.mixin.transformer.MixinPreProcessorStandard.attachShadowMethod(MixinPreProcessorStandard.java:412)
	at org.spongepowered.asm.mixin.transformer.MixinPreProcessorStandard.attachMethods(MixinPreProcessorStandard.java:340)
	at org.spongepowered.asm.mixin.transformer.MixinPreProcessorStandard.attach(MixinPreProcessorStandard.java:299)
	at org.spongepowered.asm.mixin.transformer.MixinPreProcessorStandard.createContextFor(MixinPreProcessorStandard.java:277)
	at org.spongepowered.asm.mixin.transformer.MixinInfo.createContextFor(MixinInfo.java:1291)
	at org.spongepowered.asm.mixin.transformer.MixinApplicatorStandard.apply(MixinApplicatorStandard.java:203)
	at org.spongepowered.asm.mixin.transformer.TargetClassContext.apply(TargetClassContext.java:437)
	at org.spongepowered.asm.mixin.transformer.TargetClassContext.applyMixins(TargetClassContext.java:418)
	at org.spongepowered.asm.mixin.transformer.MixinProcessor.applyMixins(MixinProcessor.java:352)
	... 23 more

Additional context

This is the message I get in the launcher when it crashes:
The game crashed: unexpected error
Error: java.lang.RuntimeException: Mixin transformation of net.irisshaders.iris.pathways.HandRenderer failed

Code: 255

[PoohBear02]

Sodium without Iris works fine, I can see the sodium UI in the menu.

[PoohBear02]

Idk if it's needed but here is a list of all my mods: vanilla, armorposer, autoreconnectrf, axiom, camerautils, cloth-config, conditional-mixin, fabric-api, fabric-api-base, fabric-api-lookup-api-v1, fabric-biome-api-v1, fabric-block-api-v1, fabric-block-getter-api-v2, fabric-command-api-v2, fabric-content-registries-v0, fabric-convention-tags-v2, fabric-crash-report-info-v1, fabric-creative-tab-api-v1, fabric-data-attachment-api-v1, fabric-data-generation-api-v1, fabric-debug-api-v1, fabric-dimensions-v1, fabric-entity-events-v1, fabric-events-interaction-v0, fabric-game-rule-api-v1, fabric-item-api-v1, fabric-key-mapping-api-v1, fabric-lifecycle-events-v1, fabric-loot-api-v3, fabric-menu-api-v1, fabric-message-api-v1, fabric-model-loading-api-v1, fabric-networking-api-v1, fabric-object-builder-api-v1, fabric-particles-v1, fabric-recipe-api-v1, fabric-registry-sync-v0, fabric-renderer-api-v1, fabric-renderer-indigo, fabric-rendering-fluids-v1, fabric-rendering-v1, fabric-resource-conditions-api-v1, fabric-resource-loader-v0, fabric-resource-loader-v1, fabric-screen-api-v1, fabric-serialization-api-v1, fabric-sound-api-v1, fabric-tag-api-v1, fabric-transfer-api-v1, fabric-transitive-access-wideners-v1, fabricloader, facebar, flashback, forgeconfigapiport, freecam, gammautils, iris, lambdynlights, lambdynlights_api, lattice, litematica, lithium, malilib, mocap, modmenu, org_apache_commons_commons-math3, peek, placeholder-api, pride, shulkerboxtooltip, simplefog, sodium, spruceui, status, voicechat, file/My Minimal Armor 1

Know the game works just fine with all these mods (except Iris).

[Jab125]

See if uninstalling Flashback fixes the issue

[PoohBear02]

Uninstalling Flashback did fix it. Sadly i do need flashback since I make content on Minecraft TT

[Jab125]

According to the crash report, it seems to be Flashback's issue, not Iris's. You should probably open an issue there instead.

[PoohBear02]

alright, I will. Thank you!

[MalignisTormentum]

This seems to be crashing for me still. I am getting a log but not sure where to submit that. I do not have Flashback. I am using Prism Launcher with the following:

• Minecraft 26.1.2
• LWJGL 3.4.1
• NeoForge 26.1.2.29-beta

I have isolated the issue to Iris; removing it allows the game to run fine with everything else including Sodium, and I see the version as ${version} in Prism.

[Jab125]

This seems to be crashing for me still. I am getting a log but not sure where to submit that. I do not have Flashback. I am using Prism Launcher with the following:

• Minecraft 26.1.2
• LWJGL 3.4.1
• NeoForge 26.1.2.29-beta

I have isolated the issue to Iris; removing it allows the game to run fine with everything else including Sodium, and I see the version as ${version} in Prism.

Create a new issue, since it's a different problem