"Assuming they didn't make both the start and end points a teleporter to other. Lets START with a marker, in blue chalk..."<br/><br/>He pulled out a piece of red chalk and glared at it. "Or red, that works too, to make sure we aren't still looping while going up."<br/><br/>He put a big red X on the wall with the chalk, before heading back up, fully expecting to see the X after rounding the first corner.