You can also push people undergrond with defense by jumping or standing on somebody's head. Best used on noobs because they chanse you straightforward and usually dont have shiftlock. If done correctly, the player should be in the ground with their tag spining and flickering.
I don't know if you know, but there is a glitch where you can survive the reaper countdown, for this a bubble user needs to use the ability on you with just a few seconds left before the counter reaches 0, when that happens, the countdown will remain at 0 in your head, but you will be alive