IMPORTANT NOTE: my updated algorithm at https://scratch.mit.edu/projects/818706641/ is more-or-less a direct upgrade to this project, requiring fewer layers and costumes while resolving the limitation that required covering up the left side of the health bar with a label. This health bar uses no pen so it can be above sprites. (The pen layer is beneath all sprites.) It does not use a costume per health level, so you don't need to worry about users loading in 100 sprites every time they open the project. It also only uses two clones no matter what the maximum health is because it is based on percentage. The only downside is that it needs to have the text "HP" on the left to cover up the inner-workings, although it can be replaced with other art if needed. Feel free to use this in your own projects.
