Describe the bug
Crash on game start.

To Reproduce
On startup, in dev environment, with eidolon-0.2.7 in mods folder under run.

Environment
Using version 0.2.7 on singleplayer, development environment.

Crash Report
https://gist.github.com/NightmareTwilight/0b35ed81671704f7f3251db2140d0e9a

From what I can understand, the #43 will might fix the issue.

This is confirmed to not be an issue on Eidolon's side, but an issue of dev environment setup. Try adding properties 'mixin.env.disableRefMap': 'true' to your build.gradle.