Join Date: Jan 2012
Location: Not every shadow, but any shadow
My guess is heat. A big creature like that would have a heap of internal heat, like the dinosaurs did. So they need to get rid of it. As they have a chitinous carapace you'd need something that lets the heat through the armoured shell so they use a smoke stack.
I wonder if that means if you jump on their back and plug it with your finger they'd explode ?