I try break "Moon Rock"(galacticraftcore:basic_block_moon:4) by "Small Block Breaker"
crash.txt

Hi, I took a quick peek into the code and think I know what this is. Cheers,-

Yepp, wrong position specified for that ;). The maintenance release v1.12.2-1.1.3 is pushed on Curse and should be available in a few hours. Can you double check and close the issue if the problem is gone in your setup? Cheers,-

fixed