Being inspired by Gamemaker's Toolkit's first season of its mini-series Boss Keys, which is a series that looks into the design philosophies of Zelda dungeons in terms of layout, I decided to do something similarly for the Metroid series. This idea was fueled by things like item randomizer algorithms and 100%-speedruns, because I wanted to find a way to chart out the areas of Metroid in an attempt to facilitate pathing and maybe even help Metroid fangame makers to think about design and gating in their games.
A New Galaxy was, dare I say, fun. It had an interesting progression system made up of two parts: collecting powerups to be able to explore places, and defeating Metroids to unlock new planets to explore. My second 100% run on Easy was about 3 hours, but I'm certain that time can be improved!
The game can be found here.