I keep having to redo this tutorial for games with similar physics. I decided to just make it one more time, then never again. Then I will just remix this one. Open the remix! sprite, to see how to make this your own. This is also the engine that Trident Man uses!
https://www.youtube.com/playlist?list=PLy4zsTUHwGJIqB6hg-sOxiwsJn7UfuCLw Thanks to @griffpatch for everything here (Except the player, which is based off his but not officially his.)