I know NBT is super powerful. So I decided to go a different route on one of my mods to break away from the craft me craft you approach. So I have an LivingDeath event that I am subscribed to which works fine. And what the event does is when you kill a hostile mob, if you have an item in your inventory it writes some info to that items NBT. Nothing fansy but it works very well. But what I want to do is be able to rely on that NBT data to craft something else. So is there  a way to craft something and check that NBT data first. 

 

So for example if I have my item which has 18 kills saved into its NBT I want to be able to "transform" that item via crafting or using maybe a block or something (like right click on one of my custom blocks with the item kinda like Advent of Ascension) and then have that item "transform/be crafted" into another item.

 

In summary is there a way to craft an item or right click a block with the item into something else by first validating that it has the proper NBT values AND then turn it into the new item. (Even if that item is just a subItem)

2 hours ago, diesieben07 said:

For recipes you'd have to make your own IRecipe implementation.

Thanks, in doing some testing and information collecting I found more of my users wanted the ability to go "find" alters and use the item on an alter to convert it (kinda how AoA used to work), so onBlockAcitvated is what I will likely be using now. 

 

However a custom IRecipe feature might be interesting for other stuff. Thanks for the suggestion.