DaemonUmbra

Send a screenshot of your mods folder please?

In a 1.12.2 folder in your mods folder

OTG does this thing where it puts its Coremod component in a mods/1.12.2 folder and the coremod uses code from the main mod, so when the main mod is removed but not the coremod you get crashes like this.

That's a Spigot server, not a Forge server... modded blocks will not work on a non-Forge server

Looks like Erebus is broken

Please read the Logs section of my signature below and provide the appropriate log in the appropriate manner.

I think it’s time we say farewell to 1.10.2 now that 1.14 is out.

https://minecraft.gamepedia.com/Tutorials/Setting_up_a_server#Configuring_from_the_command_line

Yes, this only kills the entities in currently loaded chunks.

What launcher are you using? Please provide a screenshot.

Please don't make multiple threads for a single question.

You might think it's fine, but both Quark and OTG are complaining about being unable to apply their coremod components.

Open your launcher, make a new Profile/Installation, and select Forge from the version dropdown.

1.8.9 is no longer supported on this forum due to its age. Please update to a modern version of Minecraft to receive support.

Please read the Logs section of my signature below and provide the appropriate log in the appropriate manner.

Should this question be read as "Can I annoy popular modders about updating their mod yet"?

I'm seeing errors from multiple coremods. About the only thing you can do is start removing mods.

Is this a pre-made modpack or did you make it yourself?

A low FPS rate is unlikely to have any messages in the log unless something is metering it.

GitHub Gist accepts the most, if you've maxed that out I'm impressed.

So go to the .minecraft folder in your instance folder...

Oh... dark theme made that hard to see. Anyway you should not rely on a mod to bring up the log for you, my signature has info on the location of logs, please read it.

More or less. Honestly a complain about this isn't going to take seriously by the dev team unless some proof is show from proper dedicated tools instead of Minecraft's debug screen.

Instead of "java" try the full path to the Java 8 binary.

You may have Java 8 installed but it's now what your Computer is choosing to use, try using the full path to the Java 8 binary instead of just invoking 'java'