After you get the Varia Suit in Brinstar, you can continue to a new destination in Norfair.

Norfair

Go down to the bottom of the room and stand in front of the door on the left, then run to the right while shooting. When you are about to fall in the acid, press down to crouch, then jump and press right to Shinespark through blocks on the right. When you hit the angled floor and start running again, shoot to the right to open the door so you continue Speed Boosting through it. You'll break through the Boost Blocks in the floor. Go down and go through the door on the left, and go left in the room until you're standing to the right of the acid pit. Run to the right while shooting your beam to break through the blocks on the right and open the door, and you'll break the Boost Blocks in the floor of the next room. Go down through the new opening, then go through the door on the left.

Go left through the room and go through the door. Heal up with the Chozo Statue, then go through the tunnel in the bottom of the room to reach the next room.

Go to the left and use bombs to break through the first barrier, but use a bomb just after that barrier to break a hole in the ceiling. Jump through the hole, then go to the left and use bombs to reach the ledge on the left. Make sure not to fall into the lava down below, because it's stronger than acid and will damage you even with the Varia Suit. Jump to the left and go through the door on the left.

Shoot all the blocks that you can get rid of in this room so you have a clear path to Speed Boost from the right door. When you reach the top of the slope, jump and you will destroy the Boost Blocks on the left as you go through. Go left and down, and go through the door.

Kill the Sidehopper and go through the door on the left, and use the save room if you wish, then go through the door on the left.

Go through the left door, and make your way to the left through this room, freezing enemies to use as platforms as you go. Go through the door on the left.

Go down to the bottom of the room and shoot the left door and go through. Use the map machine, then exit the map room.

In the lava below, you can see enemies crawling up through a hole. Go down through that hole. Shoot through the wall on the right, freeze the enemy that is going side-to-side, and go down to the bottom of the room. Go through the door on the right.

Jump from platform to platform through this room and go through the door on the right, then in the small room, go through the door on the right.

Go right, kill the monsters, shoot through the tentacles, and use missiles on the tentacle that is holding a monster. Later, a tentacle is holding a purple monster. You can use normal shots to get rid of that one. Go through the door on the right.

You can optionally go through the door on the right to save the game. Then go through the left door. Shoot the floor near the left door and go down. At the bottom, go through the door on the left.

Use a bomb on the left wall, kill the Sidehopper, then bomb the left wall and shoot a missile at the left door. Go through.

Shoot the egg and take the Wave Beam. This beam can pass through solid objects. Heal up with the Chozo Statue, then go through the door.

Don't bomb the wall. Use charged shots to hit the Sidehopper through the wall with your new Wave Beam. After the Sidehopper is gone, bomb the walls and go through the door on the right.

Go up and shoot through the block in the left part of the ceiling, then go through the door on the right, save the game, and go through the door on the right.

Jump over the gap, then start running to the right while shooting your beam. Your Speed Boost will break through the Boost Blocks on the right side. Go through the door on the right.

Go through the tunnels until you're under the creature that is trapped in the wall. Aim upward and shoot the creature with the Wave Beam until it's gone. Go up into the tunnel where the creature was. Go to the right, and another creature will charge toward you. Shoot at it to make it go back. Then wait for the creature to rear up, and drop a bomb near it, then go to the left. If you time it correctly, the bomb will explode on the creature's underbelly and damage it. Repeat this until the creature is gone. Before you leave the room, stand in the creature's outer shell and shoot upward at the ceiling until you reveal an Energy Tank. Shoot a missile to break the block beneath the Energy Tank so you can get it. One more thing before you leave the room: go to the left and make a running start to the right while shooting. You will Speed Boost into the room on the right and break through the floor, where you can get a Missile Tank.

From where you got the Missile Tank, go down to the bottom of the room. Go through the door on the left, save the game if you wish, then go through the door on the left.

Go to the left, shooting monsters and tentacles. If regular shots don't work, use Missiles. Then go through the door on the left.

Roll into the tunnel on the left and you'll fall through Pit Blocks. Bomb the wall to the left and go through, and you will encounter a mini-boss: Ensnared Kiru Guru.