Possibly broken like everything else.
Wait a second... if you fire a ball at the enemy, how on earth can it bounce BACKWARDS toward your own line? It's like the earth temporarily switched to some kind of alternate dimension where everything is opposite...
Now i'm going to have to develop mortars just to see if it really happens, because i have a hard time believing it. Never used a mortar actually, never saw the point when i had mobile howitzers which essentially do the same job and can be moved around the battlefield.
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