by process of elimination, I had my recent crash down to this mod and it's library counterpart. I run OpenJDK9 for performance reasons, and I encountered a bug with this and forge. Heres my log file. I'm unsure if it was totally this mod, or both it and forge. Its working now that I removed the mod though.
debug.log

Examining for coremod candidacy OpenModsLib-1.7.10-0.10.1.jar
You are using 1.7.10 version of OpenModsLib on 1.12, nothing to do with Java 9.

oops my bad haha sorry, honest mistake. Haven't slept for a while and I wasn't paying attention.