[please forgive me if my spelling is wrong, English is not my native language]

Description:

I am in the process of updating my server and the associated modpack.

Before, I run AbyssalCraft-1.12.2-1.9.4.11 with forge-1.12.2-14.23.4.2705 and everything was running fine.

Now, I try to run forge-1.12.2-14.23.5.2768 with updated mods and I have client-side crash when an AbyssalCraft mob spawn or is loaded from the map (seen with Depth Ghoul and Lesser Shoggoth). The problem exists with AbyssalCraft-1.12.2-1.9.4.11, but also with AbyssalCraft-1.12.2-1.9.4.14 and AbyssalCraft-1.12.2-1.9.4.15

Strangely, the client crash only with a copy of my server map, if I run the server with a new map I don't have problem apparently. I don't crash my client if I spawn manually some Depth Ghoul or Lesser Shoggoth in the server and the map run fine if I load it in client. If I spawn one of this mob with the client and load the map with the server, I crash my client at connection.

So, I am a bit confused and I don't understand why this crash is happening. I don't know if the problem is with AbyssalCraft or if it's an incompatibility with another mod, my test or the error itself doesn't help me much.

Mod List:

This is my precedent client mod list : https://pastebin.com/vSgX4bF9
This is my precedent server mod list : https://pastebin.com/Kq3jFGkP

This is my updated client mod list : https://pastebin.com/hb3xCNzx
This is my updated server mod list : https://pastebin.com/2A7ZRUgf

Note : I have "Sponge" server-side and "Better FPS" and "FoamFix" client-side. I have tried without these mods, the client is crashing as well.

Crash report:

Server-side log : https://pastebin.com/Y9ERKfhs
Client-side crash : https://gist.github.com/Goju-Sulfam/7a3c6140f24720dbb02d5347dad10eef

Affected versions ("latest" is NOT a version):

• Minecraft: 1.12.2
• Forge: 1.12.2-14.23.5.2768
• AbyssalCraft: AbyssalCraft-1.12.2-1.9.4.11, but also with AbyssalCraft-1.12.2-1.9.4.14 and AbyssalCraft-1.12.2-1.9.4.15

The client-side log is not a crash report, and I can't see anything in either log that would explain this behavior.
EDIT: just noticed the client log was truncated, checking out the full file now.

Yeah, it seems like it should be on my end, but I have no idea how that code could be crashing (the part in question hasn't changed in several years). Only thing I can think of would be if something in Forge changed, but that might be a long shot.

EDIT: Running an instance with only AbyssalCraft on a server with that Forge version doesn't trigger a crash, so I don't think that's the reason (then again, this seems to have some connection to your server map). You could make an instance of the server map with all of the old mod versions, and only update Forge, but that might not produce a crash.

I have made an instance of the previous version of the modpack/server and just updated forge (1.12.2-14.23.5.2768-universal), ImmersiveEngineering (0.12-87) and ImmersiveCables (1.12.2-1.3.2).

Everything seems to run fine, the problem doesn't show in this configuration. So, I think it's a conflict with another mod. I will try to update all mod one by one.

Closing this for now. Feel free to re-open if necessary.