Tyronis | Portal Pro: fall_bts Full OOB Route - Big Timesaver @Tyronis | Uploaded September 2013 | Updated October 2024, 1 hour ago.
Hitting the level load while inside the portal causes a save glitch (The other portal must get unloaded). With this you can fallunder the map and then stop the glitch by putting down a portal outside the wall. Then just portal by the exit and PBF back inbounds. This should save a ton of time as it skips the entire chamber.