I tried to make a scrolling pen platformer engine using the least blocks possible and this is the best I could do(without ruining gameplay). But maybe you can improve it? edit log: 18-6-2020: small improvement with the x movement (120 blocks) 26-5-2020: It now only has 121 blocks I didn't do a big improvement it was just something which wasn't needed for the current version. 25-5-2020: shared (126 blocks)
100% by @Rens2 Feel free to remix. "improved" version: https://scratch.mit.edu/projects/399140427