Here's my latest project: a level editor! Switch between different types of terrain by pressing numbers, and make whatever you want! It's not just one level, either. You can navigate between different areas using the arrow keys to create a full game! I'd play in full-screen. Arrow keys to move, C to dash. The hotkeys are shown in-game, but here they are: 1 - ground 1 2 - Ground 2 3 - Red 4 - player spawn (if a player spawn is not put down, your player will spawn in the center of the map.) 5 - High bounce 6 - Lower bounce 7 - Double jump ability 8 - Dash ability 9 - Goal block Press p to exit playing mode. You can save both individual levels as well as full maps. Simply open the menu, hit "Save level" or "Save all", and then copy the save code. Make sure you have the full save code if you hit Save all. It should end in an exclamation point. Have fun! Post level codes on this forum, not the comments: https://scratch.mit.edu/discuss/topic/425099/
Want to see an example level? Check out the forums: https://scratch.mit.edu/discuss/topic/425099/ This took a ton of work to figure it all out, and I spent a lot of time on this. In fact, I was working on parts of this back in May, but only now got around to finishing it. Thanks to: me from like 2016, who designed the save icon I used here. Me now, who made everything else Scratch for making all of this possible.