This following glitch works as of version of 22. February 2024.


1. Enter any Arena stage you want to beat
2. Let yourself be damaged/grabbed by the nearest enemy.
3. As soon as the damage animation is finished, pause the game and exit it to the Arena stage selection menu.
4. Chose the level again.


Congratulations! At this point you will be unable to receive any damage so go ahead and grab those Extra Costumes before the dev patches this out :)