Registering your block (plugin_init.txt)

Add a plugin_init.txt file to tell the mod which new IDs your addon introduces. Include only the lines you need:

block_id=my_lucky_block
sword_id=my_lucky_sword
bow_id=my_lucky_bow
potion_id=my_lucky_potion

Each ID becomes a real registered item/block under the lucky namespace (for example lucky:my_lucky_block) and shows up in the creative menu. If you omit plugin_init.txt, your files instead extend the default Lucky Block.