Shows a way to bypass the keys and reach the exit area somewhat faster in Doom II level 11, Circle of Death ('O' of Destruction). Note: This is the same general procedure as seen in https://youtu.be/p6TtuYhneDI but without the detour to grab a radiation suit.
This involves using the edge-activation exploit on the switch that lowers the barrier blocking access to the northeast quadrant of the map. Once it's down you can strafe-run across the gap to the platform leading northeast.
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