Arrow keys to move up arrow to jump etc. you know how to play ...okay jokes aside this is actually the entire video in Scratch. I converted the video to a 320x180 gif at 5 FPS (2 gifs actually, it wouldn't import the entirety of the first one to a sprite), imported it into the project and made it loop through each sprite. I used Scratch 1.4 for this, which also has an option to compress sprites and audio. Without compression, this project would have been way too big to upload on Scratch. This uses 30% JPEG quality on the images and "Low" quality on the audio. Song and video by Rick Astley.
It might take a while to load, be patient.
