You know what to do! But in case you don't know: Press up 2 times, down 2 times, left, right, left, right, then B, A and finally, Enter. How was I able to use the Enter key, and more importantly, know when these keys are pressed in order? Well, look in the notes and credits section.
Credits to Joshisaurio for this thing: https://scratch.mit.edu/projects/672382073