I like this mod but not enough to prioritize it. Hope this helps future users.

https://gist.github.com/P3rf3ctXZer0/9fe92c79885d324835427dc84a639d11

Details:
Minecraft Version: 1.12.1
Operating System: Windows 10 (amd64) version 10.0
Java Version: 1.8.0_144, Oracle Corporation
Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Oracle Corporation
Memory: 1557715832 bytes (1485 MB) / 8385986560 bytes (7997 MB) up to 8385986560 bytes (7997 MB)
JVM Flags: 9 total; -XX:+DisableExplicitGC -XX:+UseConcMarkSweepGC -XX:MaxGCPauseMillis=40 -XX:CMSInitiatingOccupancyFraction=70 -XX:+CMSScavengeBeforeRemark -XX:+AggressiveOpts -XX:HeapDumpPath=MojangTricksIntelDriversForPerformance_javaw.exe_minecraft.exe.heapdump -Xms128m -Xmx8064m
IntCache: cache: 0, tcache: 0, allocated: 13, tallocated: 95
FML: MCP 9.41 Powered by Forge 14.22.1.2485 Optifine OptiFine_1.12.1_HD_U_C5 124 mods loaded, 124 mods active

Whether a core mod or not it seems its only triggered when futurepack is enabled. I have about 217 mods playing nicely together.

did you try the new version ?

Still loading.

I promise to report the results.
If it helps the modder of Twilight forest had a similar issue back in 1.7.10 days.

Its fixed.

Hmm, sorry if I ask, but why do you thing futurepack caused this? Did removing the futurepack fixed this? Also I currently wonder why forge is not accepting out signature...

yes, removing this mod prevented crash.

Not sure ... I will test it later I just know that it breaks my modpack. I am sure its a mod interaction.

Does this also happen with only futurepack installed ?

I think this was most likely caused by a coremod. Vanilla code can hardly crash there.