Also to mention there's barely any plot and the character development is non-existent, except when they do stuff with your 10 ai supercomputers or that one baby Metroid.
Basically all of Metroid is a space oddysey with confusing map layouts and first person shooty action. Sure they pulled it off with prime echoes and hunters, but after playing all three you realize how all of them are basically the same plot and same gameplay: kill alien infestation/kill space pirates, get rockets, get morph bomb, get ice beam, kill boss, etc