Journey to Gensokyo is the official content mod for DanmakuCore. Journey to Gensokyo will add both normal mobs, items, bosses, spellcards, and more. Journey to Gensokyo is currently in active development, and as such there are many things that will either change, or are not implemented yet.
If it wasn't clear already, Journey to Gensokyo requires DanmakuCore.
Currently in Journey to Gensokyo
I found an ore/old spell/gensokyo notes/other stuff, and I can't figure out what I can do with it?
Not everything in Journey to Gensokyo is implemented yet. A bit of the world gen was added in the first update so that worlds didn't need to be regenerated. Eventually they will have a use. For now they just look pretty.
How can I use the Danmaku Crafting Table?
Experiment. I'm not going to give everything away. I can give a few pointers though. There are a few different slots in the crafting table. There is the amount slot, which controls the amount of danmaku created per shot, there is the pattern grid, where you can specify the pattern to use. There is the copy slot, which copies danmaku. All of these take bullet cores. Then there are the two main slots. The slot that takes the danmaku to edit, and the catalyst slot, where you put another item, and see if it modifies the stats of the danmaku. For example fire charge might make the danmaku a bit more fiery.