Logs:
latest.log

Crash report:
crash-2021-01-05_11.43.50-client.txt

You must manually install Geckolib (for fabric) to play with the aether mod.

Duplicates: #74

I did have geckolib installed in my production modpack, however it's 2.0.0 due to incompatibility with Ars Theurgia with 3.0.0

Update: Loads now with Geckolib 2.0 and 3.0 in the same instance. Closing this issue.