As I mentioned, I am getting java.lang.NullPointerException every time I try to access my own item group or reaching the end All Items or when I give Infused Soul Shard using /give command.
Other items and blocks work fine. Infused Soul Shard is somehow causing game crashes. It works fine when I comment rows 55-169 in items.InfusedSoulShard.
I think that problem is in tooltips, but I'm not really sure. Could anybody help me please? Here's link to my project with log enclosed.
https://github.com/apocalypse3000/jassa