TheDirtyDog

So despite me being a complete gradle newb I figured it out. The mod in question is an API/Library for some other mods I'm building. I only have the API and another mod at the moment and I was getting the error in the other mod that depends on the API when I called a function in the API which accessed ItemGroup.GROUPS. The problem was that in the mods build.gradle I was including the API in dependencies with compile instead of deobf and linked in my obfuscated jar instead of my dev jar. Thank you DaemonUmbra for the quick reply to my post and for your willingness to help with the issue.

When I use net.minecraft.item.ItemGroup.GROUPS in my mod it crashes with a java.lang.NoSuchFieldError: field_78032_a It noticed it in [1.13.2-25.0.214] so I updated forge today to [1.13.2-25.0.215] and still had the issue. If I remove my attempts to use net.minecraft.item.ItemGroup.GROUPS the mod works again. The crash report Pastebin can be found here.