Nintendo's E3 presentation briefly showed "Metroid 5" before introducing the game as "Metroid Dread".

I haven't finished any of the metroid games, so it's not obvious to me which are the "main" entries in the 2D series. I assume the prime series is separate, but even removing those there seem to be 5 games already:

1. Metroid
2. Metroid II: Return of Samus
3. Super Metroid
4. Metroid Fusion
5. Metroid: Other M

Metroid: Zero Mission and Metroid: Samus Returns are remakes, so I guess don't count. I know folks don't like Other M, so maybe that one also doesn't count, but I'm not sure why it wouldn't. Is it not canon?

Help! :)

In the intro of Super Metroid the title "Metroid 3" pops up, the same happens in the intro of Fusion with Metroid 4.

I mean take Other M out back behind the barn and be done with that.

Other M was never considered Metroid 5. Not sure why, from a technical or business perspective.

Other M is in its on timeline which is called "The Baby" timeline.

So, the chronology of Metroid games goes: Metroid, Metroid Prime, Metroid Prime 2: Echoes, Metroid Prime: Hunters, Metroid Prime 3: Corruption, Metroid Prime: Federation Force, Metroid 2: Return of Samus, Super Metroid, Metroid: Other M, Metroid Fusion, and finally, Metroid Dread.

Metroid: Zero Mission, Metroid 2: Samus Returns, and Metroid Prime: Pinball area all remakes.

Now, Nintendo only adds a number to the titles that advance the story chronologically. This means that interquels such as the Metroid Prime series or Other M are not given a number.

So, the games that came last in the timeline at their time of release are Metroid, Metroid 2: Return of Samus, Super Metroid, Metroid Fusion, and now Metroid Dread. In fact, at the beginning of Super Metroid there is a title screen that reads "Metroid 3" and at the beginning of Fusion is a title screen that reads "Metroid 4". I assume this will still be the case when Dread comes out.

tl;dr

1. Metroid
2. Metroid 2: Return of Samus
3. Super Metroid
4. Metroid Fusion
5. Metroid Dread

Thanks everyone!

I should play Super Metroid.

Is Metroid the only Nintendo franchise that has a somewhat consistent narrative across several games?

Sure would be great, if one could play every entry in the series on a new, handy platform that a lot of people currently own.

But then again, I like a lot of things about Super Metroid but I've never finished it, despite a good number of attempts, so I'm not sure how likely it'd be for me to enjoy the other older games either.

I'll very likely give Dread a try though, once it's out.

It isn't a mystery:

Metroid

Metroid 2 (game boy)

Super Metroid

Metroid Fusion (like the trailer for Metroid Dread, it literally calls it Metroid 4 in the opening)

Reminds me I need to dig through some boxes and look for my copy of Metroid Pinball.

@apewins: More or less. Zelda could be considered, but it's... arguable. There's the whole timeline thing and Nintendo did clear big parts of that up with that big Zelda encyclopedia book that came out a few years ago. But as far as like, a consistent linear same protagonist moving from story to story chronology? Yeah, I think Metroid is it.

I kind hoped they would also release Samus Returns on Switch, but I guess I will just have to find AM2R somewhere on the internet

Super Metroid is 3 and Fusion is 4. They got the numbers before you start those game proper.

So... here's the thing about original Metroid and Metroid 2.

They kinda aren't great.

I mean, Metroid 1 in its time was great, sure, but it doesn't hold up thanks to the lack of a map, the kinda ridiculous difficulty, lack of save rooms, you only start with thirty health, etc. I've never finished it and I don't think you really need to play it outside of curiosity about what it's really like.

Metroid 2 was a Game Boy game and it really shows. It controls fine, from what I remember, but the camera is zoomed up real close on your character, there's no map again but this time many of the areas look the same so you could easily lose where you are. You can save in Metroid 2 but that doesn't do much for any of its other issues. You can only have one beam at a time and if you need a different one, you have to go find a different one and that's a total pain.

Just play their respective remakes, Zero Mission and the fan-made AM2R (the official 3DS remake of Metroid 2 is not, in my opinion, a good game. It's not garbage, but I don't think it's anywhere near the quality standard of the rest of the 2D games).