Error when killing Evoker

When I kill Evoker from Raid, the game cause massive lag and drop fps to about 0.1 fps.

If content log history enabled, it will show  errors like if it were part of addons, but I don't add any behavior Pack to the world.

The error shown are "[MoLang error] can't find variable.r, variable.g, variable.b, and variable.a"

 

It happen several times and sometimes crash the raid