Metroid : Walkthrough 3

At the MAP, POINT location, if you destroy the second-from-the-right spot with a bomb, you can descend below! Use bombs 2-3 times to progress downwards and obtain the High Jump at the gate ahead! You'll gain a jump height 1.5 times greater than usual!

After obtaining the High Jump, proceed forward from the lower part of the statue. Advance to the left while using bombs.

You can go to the upper level from the MAP, POINT location!! Jump at the timing when the blocks regenerate and proceed to the upper level. Let's obtain the Screw Attack at the gate ahead!! When performing a lateral jump, Samus will rotate and be able to attack enemies!

Return along the path you came from and head back to Brinstar. The attacks are intense, but please do your best. ※If you get a game over, you can continue back to the elevator.

At the POINT on the map, there are four tube-like areas that you pass through with the Morph Ball. Aim for the top or second from the top. Enemies also enter these tubes, so proceed while dealing with them using bombs.

At the POINT on the map, you can destroy the ceiling in a hidden passage. Without the High Jump, you won't reach the left gate, but you can advance now. Obtain the Varia Suit ahead in the room on the left.
※It's possible to clear the main story even without the Varia Suit.

Proceed straight ahead to the right from the point where you broke the ceiling, and you'll find a "Missile Tank". Obtain it.

Proceed further to the right from the Missile Tank in Chart 16, and you'll reach a dead end. There's a breakable ceiling, and by going right from there, you'll find an "Energy Tank". Retrieve it. All items have been collected in Brinstar! Next, proceed to Kraid.

Proceed following the arrows in the image to advance to the next area, "Kraid's Lair". In the POINT area, destroy the floor with bombs and continue forward.