I thought that the Metroid franchise deserved more than just a space theme so I made this:

This is mostly retextures but some enemy physics have been slightly modified to fit the Metroid universe better, so be aware that a few levels online might become impossible to complete (though very unlikely).
Mario's abilities are still the same. No Player Action Table edits here.

The update that I've been working on for a while has now been released, although you can still expect some minor tweaks in the future.

Todo list:

-Enemies will be given their real sprite size
-Backgrounds in the NSMBU style will have several layers
-NSMBU lighting on enemies will be disabled
-SMW will have its own coin icon
-NSMBU Peach cutscene background will have parallax scrolling
-SMW backgrounds will have some animations
-NSMBU 3d models will be replaced
-Sprite effects will be edited
-Thread screenshots will be updated

And before someone asks, no I will unfortunately not make a Switch version of this mod as SMM2 presents many technical difficulties and cannot be easily adapted to the Metroid universe but if someone else wants to port it, knock yourselves out !

Anyway, have fun !