I reached this part today, and I think I understand the confusion. There's a part where you're required to jump in a liquid pit to continue, but I think it's just water, because it doesn't damage you. It can be confusing on a monchrome display.

I surprised to see so many people resorting to maps in order to beat this game. Not that it's a bad thing, but in the multiple times that I've passed it (on an original cart), I've never had to resort to a map to find my way...

I'll definitely be picking this game up when I get a 3DS of my own, despite owning it already. It'll bum me out that I'll have to play it in black and white (since I'm so used to the added color playing it on a GBA gives it), but it'll be worth it, especially since I know there'll be no issue with the save battery eventually giving out...

No, I actually was taking damage from the place I dove into, and was nearly dead when I made it out! I will have to replay it some time and see if I can figure it out... but that's not going to happen any time soon.

Apologies to Theblackdragon, but here is my impressions on Metroid II I made earlier today, have a read please.

Hey just bought and completed Metroid II the other day and I was pretty pleased how much depth it had for a GB game. I loved the whole overworld and I though it was a great bridge between the original Metroid and the awesome Super Metroid. So far i've played all the 2D Metroids, which I prefer over the Prime games
(i'm not really into first person adventure games) and i've also played Other M of course. I don't know why everyone bashes Other M for the Portrayal of Samus, but I thought her femine side had to come out, I mean there has practically been no backstory of Samus before the orignal metroid, unless you count both Metroid Zero mission and the Metroid manga. I, for one thing enjoyed both the Narrative and the gameplay and I don't see any reason why people loved to hate on it.
I'm still waiting on Nintendo to produce another excellent 2D Metroid and i'm certain they capable of pulling that one off, since Other M isn't the last chronologically. Those of you that have played Metroid Fusion recently from the ambassador games or like me played the game when it first came out, know for a fact there is a good story waiting to be told after the events of fusion and I won't give the ending away or any spoilers for those who haven't played yet, but it I can say it involves a deep conspiracy and who knows whether the Metroids will be in it or the X, but of course it wouldn't be a Metroid without the aforementioned alien parasites.

Anyway, I read a review in the March AU/NZ edition of Official Nintendo Magazine of Metroid II that only gave it 78%! It seems the only thing they didn't like was the background music and the Monochromatic graphics, which actually IMO give the game a more deeper, darker atmosphere. I Loved Metroid II and I reckon it deserves at least a 90%. It as been one of best 3DS VC purchases for me so far and I recommend it to those interested in the 3DS' VC. If you loved Metroid II you'll also love Kid Icarus: of Myths and Monsters, which is the sister game to metroid II, since both the originals and the sequels both run on the same engines on both the NES and the GB. While I mention it, Kid Icarus: of Myths and Monsters is a great lead up to Uprising, which I am purchasing today, very soon.

This game finally clicked for me.

I'm stuck. I only have 13 Metroids left to kill, and I have the lava level completely drained, but there's a little wall in my way (like two or three little black squares), but there's no way to destroy it, or go around it.

I'm only 1 missle tank away from being able to carry a max of 200. Do I need that number for some reason (that would require me to search every inch of the game world, and that could take forever)?

The game never requires you to have a certain number of missiles.

I think I am in that area about the lava. I Lava swim in two different spots and there's a Metroid at the end of them, however I can't go back seeing as I will die. I am missing 2 Metroids. I have the Plasma, 4 Energy Tanks, 200 Missiles and the Space Jump.

I got past that area. Just had to shoot the blocks with missles (had no idea why I never tried that these past few months, lol).

Down to only 11 Metroids left, but I'm stuck again. I'm in a pitch black room, stuck in morph ball form (no where in this small room is large enough for me to jump or stand up), and bombs aren't getting me out...

Yay! I got out! Now only have 10 Metroids left, and I got the Screw Attack!

3 Metroids Left and I DON'T have the Screw Attack... I know where it is though!
Edit: WOOT BEAT THE GAME!

Just for the record, though I, too, lava swam to kill several Metroids (and what tense fun that was), I'm told this is actually unnecessary and the game supposedly never forces you into the lava.

It's true.

After reading this thread I decided to get this game, and it's great! Much better than the NES Metroid!
Just a question, after getting a beam upgrade, it replaces the old one? Because it seems to... Is there a way to select one? Or do I need to go fetch them back or something?

I forget if it replaces or stacks. If it replaces, I think you can go back and get it from the same place... but I'm not sure.

I know this has been extremely helpful, but I can tell you for certain that the beams are made available multiple times in the game, so there is no need to go back.

They replace and they aren't needed but one that I know why you will need and it will reappear twice so you don't have to backtrack to get it.

Oh well, I guess that's why my beam wasn't freezing enemies anymore then.

So I'll find any necesary beam again? Well, that's good to know.

Beat the game! That Queen Metroid was a piece of work!

@Morpheel, as others have said, the new beam replaces the old one (but you can go back and get the old one). Also, near the end of the game, theres an area with a lot of Chozo statues, each with a different beam type, so you can get your preferred beam back there, as well.

This is oficially the first Metroid game I have ever completed (the only other games I have played are Prime Hunters and Fusion) . It was fun and not confusing at all, unlike the NES game.

I played it old school, without save points (though I did use the sleep function _{[But I always paused the game first for some odd reason]}) and I completed it in 4:44 hours (the worst time of the day in Japan) and my ending sequence was Samus running -> jumping -> standing there. According to my journal though, it actually took me 7:18 hours to complete it D: it surely felt like less than that, I'll try to get a better ending next time.

Also, I think I read somewhere that the ball jump and the gravity suit appear in this game? I never found them.

Oh and I found a small harmless bug, this is what happens when you go up on these water currents n.... It seems it leads you to a room that doesn't exist or something.

The Ball Jump are the VARIA suit are in the game. I think I found all the items.