sry midway through writing this i have been asked to do something<br/>so here it goes:<br/><br/>On the course, Runner got stuck inside a chamber and found that even though the portals can be passed from either side and you just come out the corresponding side of the other portal, he couldn't go through a portal that is allready occupied even from the other side.<br/><br/>Lets call the orientations of the portals A and B, meaning if you chose to pass through from the A side, you'll come out of the A side of the other portal and B leads to the B side of the other portal.<br/><br/>If the portals are put down parallel, centered and very close to each other in an A|B A|B orientation, the material that tries to pass through will hit itself as it gets redirected. this would only work if the length of the object trying to pass through is longer than the distance between the portal. Kinda like this:<br/><div class="spoiler_container"><div class="spoiler_header" onclick="hideSecond (this);" role="button">Spoiler: Click to Show/Hide</div><div class="spoiler_body">(https://i.imgur.com/RkhBIEf.jpg)</div></div><br/>This would effectively make a shield that redirects anything into itself if it's long enough. A bullet that's only a few centimeters long would leave the portal before entering the other if the portals are too far apart from eachother, resulting in moving straight through as if nothing happened (the only thing that would change is it's direction on a short distance, namely between the portals)<br/><br/>My thinking was that this could be learned by Runner after extensive use of his power. Does this sound ok? :D<br/>I hope this made sense<br/><br/>Addition: For no real reason other than how i thought this would work irl, i decided back then that the metal wouldn't react with anything, not even the light produced by the lighter, because if it did, everything that passed through would get heavily diluted if not sliced into a fine mist by particles or just air passing through from the other side of the portal. meaning that at the area where a portal is occupied, the material can't be interacted with from the other side.