Turbowarp: https://turbowarp.org/989568656?interpolate&offscreen&size=640x360 Tons of credit to @Gangstermango, I was heavily inspired by his projects and I highly recommend checking them out: https://scratch.mit.edu/projects/1138418230/ https://scratch.mit.edu/projects/1134849394/ https://scratch.mit.edu/projects/1139614172/ https://scratch.mit.edu/projects/1139611263/ wasn't expecting this to coincide with his latest release but hopefully it works out. Also credit to @Tomicool for inspiration, check out their engine from way back when: https://scratch.mit.edu/projects/74711180/ Credit to a bunch of friends and family for helping and listening to me talk nonsense. I appreciate it. Credits to Sega for Sonic the Hedgehog, and the genesis sprites and gameplay. Tons of credit to https://info.sonicretro.org/Sonic_Physics_Guide and the Sonic Retro site in general for a very in depth guide on sonics physics from the original genesis games, several ideas and values were pulled straight from there to get an engine that hopefully feels quite close to the original games. This engine won't be one to one and I changed a few variable to fit my own liking/purposes, so it won't be %100 accurate but it should at least feel accurate. The Sonic Retro website doesn't credit a single author but rather "Sonic Retro Contributors," so it was probably contributed to by several people. If you are interested in creating your own sonic engine, HIGHLY recommend this site, it walks through almost every single concept you would need to know in depth so it is very helpful. Also, feel free to ask around if you do want to make an engine, would be happy to provide any help I can. Credit to various programmers on scratch and youtube for some ideas and techniques that I have picked up over the years, including for verlet integration (unknown), slope detection (some inspiration from griffpatch, see However, I did not borrow any scripts directly from griffpatch.), and the atan2 function (Zro716, see here: ) Sprites were hand drawn in the vector editor but are heavily based off of the sonic 1 sprites and lightly based on the sonic 3 sprites. Credit to Sega for those sprites Studied sprite rips from spriters resource contributed by Techokami (sonic 1 Genesis for GBA), Triangly, Paraemon (sonic 3), Orbyy, Wiztoad, Troopshi (customs based off sonic 1 beta style). Level collision was hand drawn using Inkscape, as were the foreground and background. Credit to musical-artifacts for soundfonts (Kirby's Dreamland 3, Bomberman Hero) and sound effects (Sonic Rush Adventure). Credit to the Sonic fangame community for inspiration as well And, of course, credit to scratch and the various other programmers/animators/designers/developers out there. Keep doing good stuff. Thanks for playing!