Ugdhar

Do you have AMD graphics? If so, try updating your drivers from the AMD site (not MS update)

Have you tried this suggestion yet? Does it crash if you create a new world? Or only when loading an existing one? And sometimes, removing mods is the only way to find the culprit. Instead of 1 by 1, you can remove 1/2, and test. If no crash, add 1/2 of the removed 1/2 back, test. Can more or leas keep doing this until you find what is crashing. Still a lot of work, but if you don't get a solution from someone that can see what's wrong, what choice do you have? Also, please post logs as described in the FAQ, it makes them easier to read and makes the post easier to navigate. This snarky comment is not necessary, if someone knows how to help you, they will, be patient.

Please post your logs as described in the FAQ, when they are just pasted into your forums post, they are hard to read, and add the need to scroll 100 miles to get to the bottom of the page to reply etc. I assume Better Minecraft is a modpack that works? If so, and you are adding to it, add your new mods 1 or 2 at a time, and you will find which one is causing the problem.

Please post your full log as described in the FAQ, it should provide more information.

Your link will not work, as it references a file on your local filesystem, and not on the internet. Please see the FAQ for information on how to properly post your logs.

Firstly, you should really post your logs as described in the FAQ, it makes them much easier to read. Does this crash still happen if you remove the epicfight mod?

Merged your questions, you didn't really need to make 2 posts, considering they are the exact same question with 2 different subject lines. You need to use the forge version for the MC version you wish to mod. There are so many differences between versions in the Minecraft codebase, especially at certain points, that Forge had to make compatibility breaking changes to keep up.

Post logs as described in the FAQ, more information is needed to help you with tour issue. I moved your commwnt into its own topic, you shouldn't add on to someone elses post with what is essentially a "me too".

You should post full logs to show the big picture. Does it work without Optifine?

You never said what your problem is. Also, post logs. See the FAQ banner link at the top of the page for how to do so. *edit: And of course I'm not seeing the FAQ link at the top, so here it is: And no idea what this AMD spam crap is

You should post your log on a paste site per the FAQ (link in banner at top of page), it's near impossible to read the way you have it posted with all the sideways scrolling needed.

You have Java 8, you need Java 21 for the version you are trying to run.

Just to make sure, did you update your video drivers from the AMD website? That's where you want to get your graphics updates from if not. That error in the logs just looks very weird to me

Yes, then create separate Installations in the launcher so you can specify different folders for each set of mods/versions you want to run

Try posting logs per the FAQ banner at the top of the page, it might provide information that would help figure out what is going wrong. I split your comment into a new topic, because even though you said it's "the same problem" as the original poster, you have a different setup than that person, it's not the same problem.

Unfortunately those screenshots do not provide any useful information. Try to post logs per the FAQ banner link at the top of the page, they may have information that would show what is going wrong.

That log still has both embeddium and rubidium Also not sure if "reforgium" would count as a dupe of those mods as well.

Is it the same error? Or something different? If it's something different, then the dupe mod problem is that, and you've got other issues. When making a large modpack, it's always best to add mods a few at a time, and test in between, rather than add 100 mods and then try to figure out what's incompatible/breaking.

Post logs as described in the FAQ (banner link at top of page), it might have some information that will show what's happening

Good rule of thumb, is not to use fancy/special characters in file or folder names. It has a history of breaking stuff

I don't think you can use embeddium and rubidium at the same time, if you remove one does it still give dupe mod error? *edit: also, thanks for fixing the log post, much easier when you can view it in raw format!

This log is so hard to read with the line wrapping. See the FAQ for the proper way to post logs.

Very first search result on google when I search for "minecraft jinryuujrmcore": https://www.curseforge.com/minecraft/mc-mods/jingames-jrmcore

You will need to upload your logs somewhere on the internet, and link to them here. The links you have provided (file://) are for files on your local filesystem, which we cannot access. The FAQ link at the top of the page has information on paste sites you can use to share your logs.