I recently had a chase scene with giant dragon turtle too. But I managed to get away(and closed the gate, yay!) stealing worn boots and all uindetified rings in process. And my own silvery arrow that Blup's moma considered to be hers after it didn't return on the very first hit :-(

This brings up a question - do missiles never return in water cave or was I unlucky? Because currently I'm playing an archer with Thunderstroke who is like 10 times squishier.