https://pastebin.com/r5xe1EvU
the log seems to point to the mod but when i've been able to gather is it crashes with it saying
something about a leash returning a null or something with living entity?
i am using custom player models and a heavy mod pack but the pack runs pretty stable until one the following happens. when im killed either from fatal damage or i bleed out the game would stall for a moment before crashing.

the other times it's 85% of the time it would crash is simply closing the game normally.
i am using immersive portal which from im told already is laggy but it's pretty a core feature of my modpack im using so removing it would ruin the pack. i provided a link to my error log in pastebin so that you can review the error chain. i love alot your mods and plan to use them all here but i wanted to post this here just in case.

I can also confirm im using a good amount ram allocation to insure that it has enough memory to run this large pack as well.