It seems this mod doesn't play nice with Marathon Mod Automated.

Link: https://mods.factorio.com/mods/faraway9911/marathomaton

I got the following error: http://i.imgur.com/bN4gz5Z.png

With some trial-and-error I found it's this mod causing it. Since that mod tries to automatically increase recipe amounts, it's probably got something to do with that process. I'm just guessing though.

I can't reproduce that error. I've tried Avatars with just Marathon Mod Automated, I've tried adding in the whole Angel's and Bob's basic suite of mods. Can you double check that all of your mods are updated, and if you're still having issues I'll need a list of mods that cause this crash.

Everything is updated. I'm using a long list of mods (including Angel's en Bob's), so you're right to search in that direction. I just copied my JSON to pastebin, is that alright?

https://pastebin.com/Bue5HbZB

However, I just tried the following, with no changes to other mods:
Avatar on/Automated Marathon off: No error
Avatar off/Automated Marathon on: No error
Avatar on/Automated Marathon on: Error

Edit: In case you find that errors are to be expected with such a mess of mods, I understand if you're unwilling to see what combination conflicts. Especially since you have difficulty reproducing it yourself as well.

Ok, how about this, can you zip your mods folder and send it to me? Either email to DedlySpyder@gmail.com or upload it somewhere with a link.

Either way, I'll look into this either sometime late this week or over this weekend.

Found the issue, it is with marathon mod automated. I've made a post on the mod portal page for it.

That's interesting - I actually have tested with Avatars and haven't seen this bug.

(I'm working on marathomaton) Will continue to investigate the root cause. Can also push out a patch in the meantime.

Patch pushed.

Yes, I'm not sure which combination of mods requires it, but it somewhere between Angel's/Bob's (plus our 2) and that list of 100+.

Thanks DedlySpyder, and I hadn't even sent the zipped up mods yet. Shame on me.

Great job though. faraway9911, with your patch of automated marathon everything works again!

Oh, and it's not actually 100 activated mods. Most are toggled off. Still 50 or so, though.