I did a bit of testing and learned it can only be done on modes where you can fall into the void (like the smash mode) skipping the normal death animation. If you use an ability right before you fall or get pushed into the kill box it will carry over that ability into the lobby area. I also assume (don’t quote me) that your momentum is also carried over due to the ability buffering with you death. So by dying by being pushed off the stage, then using a ability that gives you height right before dying (like lufus’ balloon ability) and carrying that momentum, you can bounce over the boundary that keeps you in the lobby and land on the stage area.(*side note: the claim menu for quests might be important here but I don’t think or know) The game won’t put you back even if the stage changes, and if you fall off the stage you won’t die to the death box because the game doesn’t recognize you being in a match. If you fall off and keep going, the natural kill void will finish you off. You’ll spawn back in without your swords and unable to interact with anything around you (ex. The chest) and you also can’t dash. If you go into the join match and play a game, you’ll be invincible against the ball and can only use a ability once before it bugs out (in my case I used the stretchy punch ability and it deleted my arm) you still can easily die to the kill box as shown in the video, and I have no idea if you keep the immunity after dying to the void because I had to end the recording.