You run blindly in the direction you think the door is, but all you find is bats. If only you had your matches! But your pack is gone - you might fight without it.
Your shoulder hits stone, jarring your body. You feel along the wall until you find a door - you've no idea if it's the one you came in by or the other one. You push, but it seems to be stuck fast!
The bats are still clawing at you, and you feel warm liquid trickling down your arm. You need to get out - fast!
You give an almighty push, and the door springs open, throwing you out through it. You loose your footing and crash down the stairs you entered by, the bats streaming after you.
Your head hits stone again and again and again. Your skull cracks, and bats swarm up your body.
You have failed to retrieve the diamond. Your journey ends here.