Hello, so I've needed to update my modpack Pristine, and TiCon was just out for 1.12 . I added it with Moar Tinkersw loaded the game and it crashed. I then went mod by mod and i went to Chisel and it had that crash.

Crash: crash-2017-07-18_21.38.54-client.txt

This is a known bug with Tinkers Construct: #3006. It has been resolved but a new alpha has not been pushed to curse yet.

Ok, thank you

For the record, this crash is caused by a recipe with an output that has a stack size of 0. Its patched on our side so it just ignores those, but if removing Chisel fixed it you might want to verify none of your recipes have a broken output (not sure if there are legitimate cases for empty outputs)

The culprit seems to be this mod: https://minecraft.curseforge.com/projects/block-armor

Report it to them.

Thanks for finding the mod that caused it.
For me it was the one of the "Extreme Reactors" Block-Armours. I disabled them all.