No Lag! https://sulfurous.aau.at/html/app.html?id=230012607&turbo=false&full-screen=false&aspect-x=&aspect-y=&resolution-x=960&resolution-y=720 A tool to make Metroid games. Arrow Keys to Move Z to Jump X to Shoot Down to Duck, and Down again to enter Morph Ball Mode.
I used Griffpatch's platformer tutorial, but I did all the other stuff.