Brain Food

Use the save room on your right and continue to the next room, then go right through the door in that empty room.

Beware of the spawning rings (creatures that can damage you) as you drop to the bottom of the shaft, then head through the door at the bottom.

Avoid the rings in this room and head left as you meet your very first Metroid. Freeze the Metroid (a dangerous creature that latches onto you and drains your health) and shoot it with five missiles to get rid of it, then go left to the next room.

Freeze and kill a Metroid while trying your best to avoid the rings, then drop to the ground and kill a second Metroid before heading through the nearby door.

Freeze the rings and approach the lava to attract a Metroid, then freeze it and kill it. Jump a few gaps as another Metroid appears, then kill it like you did the last one. Jump over a few more gaps and kill a third Metroid, then continue on to the door. Kill a fourth Metroid here while avoiding some rings, then go to the next room.

Drop down the shaft here and freeze TWO Metroids as they approach from both sides of you. Keep them frozen and launch 1-2 missiles at a time at them until they die. If you try to launch any more than that you run the risk of one of them thawing. Head right to the wall and jump up a little to lure a Metroid down to you, then kill him and climb up the shaft. Kill the Metroid that appears on your right and go through the door, then go through the next door and use the save room.

Return to the previous room and shoot through the floor, then drop to the ground and enter the next room.

Walk to the right end of the ledge to lure the Metroid up to you, then kill it and drop down two ledges. Now walk to the right edge of this ledge and kill the Metroid when it gets close. Drop down one ledge and walk to the left end, then kill the Metroid when it gets close. Drop down another ledge and walk to the right end, then kill the Metroid when it gets close. Drop off two more ledges as you kill a nearby Metroid, then drop to the bottom of the shaft. Kill one more Metroid here and go left to the next room.

Bomb the floor and hide on the left or right side, then start jumping down platforms one at a time until 2-3 Metroids appear. Lure them up to the top and kill them, then work your way down again and kill another Metroid.

Bomb this floor and hide on the left or right side, then drop to the ground and kill two more Metroids. Now climb to the top once more and head through the left door, then use the save room and go left to the next room.

Run to the end of the room and use a missile to open the door, but DON'T go through it. Instead kill a few rings until you have full health, missiles and super missiles, then go back and use the save room before returning here.

Run to the end of the hall again and enter the next room.

In this room you need to avoid rings and turrets (automated defense systems) as you work your way left. There are also pulsing gates (barriers that regenerate if not fully destroyed) that block your path and they can only be destroyed by a barrage of missiles. However, you have to be fast because the gate will regenerate if it is not completely destroyed, which means that you'll waste missiles if you're slow.

Once you've destroyed three gates another hazard presents itself, lava. This section of the room is the hardest yet, but as long as you try your best to stay on the platforms [or climb up onto them as fast as you can] while pumping the gate with missiles you should be fine.

Now jump left and pull yourself through the narrow space to the final section of the room and a boss battle.