LogFAQs > #955073314

From what I heard after listening to the developers talk about this, they had an idea for a Metroid game like this back in 2003. They could not at the time make the game in the style and mechanics they wanted based on the technology of the time.

So it sat on the shelves for a long time then recently they dusted it off and here we have it. Probably why it's a direct sequel to Metroid Fusion, since that is the furthest game in the Metroid timeline and this would have come after that.

So even more amazing is this is the first game to advance the Metroid story into future events since 2002 when Metroid Fusion came out. The events of every Metroid game that has come out since Fusion has taken place before the events of Fusion.