[Lance]

More specifically, mousedown is an event, which is not to be placed within another conditional statement.

If you want it to drop once every time the mouse is clicked, you'd want to check for mousedown and leftmousebutton; otherwise, you'd put the leftmousebutton in a timeout.

Also, two other caveats:

-You can only lay money that you have
-It'll only work if you decrement the player's rupees, otherwise the NPC-Server will eat it