Theatlasteffect

Ok im trying to make a add a few thing's to a mod that i like but im having a lot of problems setting it up in Intellij i have already goten the mdk from forge for the version that im working on and when i add that in intelli i can launch from inside of it and it works fine but im having problems adding the second mod(main mod) into the project to cuz i think i would need it in the project so the codes could pull from the code from it, or at least i think im still very new to this. after i adding the second mod and do the build it works fine but when i try to run it, it crashes every time and im not sure how to fix it. crash message: https://pastebin.com/dgisJDQi