I have checked for any clientside mods, and this pack has worked before. I have no idea what is causing it, so I'm bringing it to here.
There is an issue with CodeChickenCore
Update it to the latest build:
I replaced chickencore with the current version, however it is still failing to launch
Add the new log
Unfortunately they now exceed pastebin's max size, so I had to put them in a .zip on mediafire
Also remove all 3 mekanism mods
how this worked is beyond me, but thank you