Guidelines

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Minecraft Version

1.20.1

Mod Version

4.1

Mod Loader

Forge

Mod Loader Version

47.2.32

Describe the bug

Whenever the Wither Storm spawns in any capacity, or even if I join an existing world before the mini-update with the Wither Storm spawned, the game completely crashes.

Steps to Reproduce

1. Start world
2. Summon Wither Storm
3. Crash

Crash Reports/Logs

https://pastebin.com/hk0mqJ5Y

Is OptiFine installed?

• OptiFine is installed

Screenhots

No response

Mod List

Definitely sounds like a mod conflict, also use Embeddium instead of Rubidium.

Yep, it worked! Thanks!

Seems like a bug with rubidium, try using Embeddium as FrozenDragon0 suggested