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.
The PCs encounter an elaborate trap room, designed to fill with water, drowning those inside. Clever and resourceful, they disable the trap and move on.
Only later do they discover that this room is part of the elaborate cooling system that prevents beasts of elemental fire from overrunning the complex. While the fiery beasts run rampant, they begin setting fires, which causes the complex to become increasingly hot and smoke-filled. Additionally, the PCs now have to fight their way out past aggressive fire creatures...