I made the engine! Use the arrows to move. Press space to use your sword or to advance text. Press o to get your save code and p to load a save code. Press 0 to open the level editor. Press a and d to navigate through the level editor blocks. Use q and e to switch between blocks quicker. Press w to quick select grass. I think the save code is finally working. Update: the game was not saving because I was signed in to @lioonj on 2 different devices. Everything is fixed now. I think the level editor works now. I am working on the font. I added music. I upgraded the save code. I got the text to work. I have almost broke it three times now. It is possible to walk backwards.
Thanks to @griffpatch for the assets and for ideas. The code is 100% me! No, really. I didn't watch the YouTube tutorial. 489 blocks last time I checked. Turbowarp link: https://turbowarp.org/727982025