Night Bird
Sure, it looks like a bunch of bones randomly piled in a cage—but just wait till dark. That's when it reassembles, regenerating both flesh and feathers—hence the iron cage. Before we managed to trap it here, it terrorized our town for generations with its firebreath, its acrid tears, its maddening song, the nightmares its eyes impart, the diseases that spread wherever its droppings fall. Having lost my entire family to its horrors, I’ve tried to kill it so many ways. If, as you say, you can dispose of this abomination for good…what can I give you to take it away?