Hidden Crossbow (3.5e Equipment)
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This is attached to a spring device that will trigger and shoot a bolt out whenever a certain gesture is made with the hand.
This crossbow functions when unfolded as a hand crossbow, triggering the crossbow (making the gesture) is a free action. When folded, it gives a +2 Sleight of Hand checks made to conceal the crossbow. Also, it has a hidden compartment in the handle of the crossbow. It can store one vial of potion, usually poison. It is a move action to access the compartment.