In the final trap room, where they had to stick their arms into the saws to fill the beaker with blood to escape the room, why didn't they just go back and bring in a dead body from an earlier room and stick their arms/legs in the machine instead of theirs??? The previous room's door was not closed, as after they saw the trap they went back into that room (when they discussed that each trap was designated for 5 people), and they already knew how to play that game before they started it, so bring the dead black girl back in with you and shove her limbs in the machine!