Old bug: kills you going down the shaft to the final boss. Happens more often now than it used to. Been a problem for a long time, apparently they don't care enough to fix it. New bug: the hatch above your head going up the tube to the next-to-last arena (the one with the 3 mine diffuses) doesn't open to let you through. This is not the same as the (still stupid) Joining Allies issue where it cuts you off if you're more than a couple seconds behind your teammate; this thing stays closed even if you're the first one there. Opens eventually. I have a video that shows both.