As far as the sling is concern the EB team seem to have it right, yet again. Slingers applied as support are best employed against, infantry based armies. Here the only reason to use the bow is either to kill the enemy leader or panic enemy troops with fire. This type of missile troop (foot based sling or bow), not nearly as effective in mobile combat. As to your question, when used overhead, you must elongate (or kind of whip) the last orbit in the direction of the target, then upon the actual release, point with your sling arm and hand just to the right of the target, as if you're throwing a stone. You do this by dropping your sling hand behind your head then jerking it foreward as you lower your torso, both in the direction of the target. But it is very important that you should know this move must be very quick. I suggest that if you're bent on doing this, at first try it very slow and at side arm, rather than over head, until you become familiar with the move.
However, this is a very dangerous weapon and I suggest you not use it, as one can very easily harm theirself or others.
CmacQ
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