You can test for player right clicking, I suggest you check video on it. Testing for the direction a player is looking (I personally prefer averaging it out by 5s, i.e. 60, 65, 90) is simple, and you can find MCedit filters for it if you're not too lazy. I'd also recommend a simple summon no velocity fireball for one of your classes. This lets them punch it in whatever direction they want it to go quite easily and doesn't exactly require any work.
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