I don't think it should hurt players. That would make it like arrows and bombs and whatnot. Not fun.
But, exhaustion would be nice. Like, after a certain amount of time, you get tired and can't use it for a while. Maybe eat bread or apples afterward?
I like the idea with tournaments and sparring, but maybe a bit less than 10 hits, around 7 or 8, because if you're in a tournament with heavy sticks, you're not going to last past 7 or 8 really hard thwacks.
Also, I think that the bamboo sticks should break, and you can repair them and add in materials with stuff from mining.
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