The Liberators of the Coin is primarily an organization Halflings devoted to (insert trickster/thieving/Halfling god). They pattern themselves after a myth of the god stealing gold coins from his brother on the evening of his wedding. The stolen gold was a part of the wedding ceremony and its absence meant that the ceremony could not proceed. The theft resulted in the trickster being able to marry his brother’s intended.
A cave with weapons sunken into the walls, blades sticking out of the floor and ceiling, and so on. Possibly, any weapon used in it could be torn out of the hand and sink into the stone.