TO LOAD THIS CART in immediate mode, type load #playback_a

VVhat's new ?
(01-17-22)
✅ New BTN() can now be called with no arguments, returns numeric of all buttons, thanks to @SmellyFishstiks.
✅ Beefed up the documentation and usage instructions.

This program will let you record and playback keystrokes, including saving your code with those compressed keystrokes in very small code indeed.
First off, the record and playback routine is 436-characters total, so this entire method is pretty small at that. Add about 46-characters for each of the functions record() and play() and you're home free !
Further I did not make this game. It is JELPI, written by @zep, a demo game which is included when you purchase Pico-8.
What I have written are two primary functions. One to record keystrokes as you play the game and transfer them to the clipboard as new source code - and the other is to simply play them back as you have listed.
This replaces the btn() function with my own. Include the 3-functions that + typing at the top of your code: _b0=btn and you are perfectly done. Nothing whatsoever else is needed. See the code below on usage: