Metroid : Walkthrough 4

After getting off the elevator, head left towards the gate immediately. Although it may seem like nothing at first glance, there's a hidden passage that can be accessed by bomb jumping. Proceed while using bombs, and you'll find a "Missile Tank" ahead that you can obtain.

Return to the elevator and this time proceed to the right red gate. Ahead, you'll find a "Missile Tank".

Follow the arrows in the image and break the dead-end wall, then proceed with the Morph Ball. As you progress, you'll find an "Energy Tank" to obtain. For the return, moving left with the Morph Ball from the top of the left pillar is good.

Follow the arrows in the image to proceed. At the POINT location, you'll see sandy terrain, which is passable, allowing you to descend below. As you progress, you'll find a "Missile Tank" to obtain.

After obtaining the Missile Tank, return to the left gate and descend through the hidden passage. Proceed to the right and defeat the "Fake Kraid"! Unlike the real one, you can easily defeat it with missiles or the Screw Attack.
※It will respawn multiple times.

Right after the Fake Kraid, proceed to the right, and after passing through the blue gate, place a bomb in the center. Descend through the revealed hidden passage, and you'll arrive just before Kraid's room.

Before heading into the room on the left for the Kraid battle, defeat the "Giga" to fully restore your energy.

Missiles or beams are often deflected by Kraid and don't hit very well! It's most efficient to continuously place bombs at Kraid's feet to deal damage. Challenging Kraid with full energy might surprisingly make it easy to defeat.
※ Don't worry about recovering health in this room as there is an Energy Tank available!
※ Defeating Kraid will increase your missile count by 75.

You can fully recover health depleted during the Kraid battle. Once you've used the beam to reveal the Energy Tank, simply bomb jump from the platform you fought Kraid on to the right to easily obtain it.

At the POINT location, you need to climb the vertically long breakable blocks with good timing. Be extremely careful as mistiming could lead to falling all the way down. Once you reach the upper level, proceed cautiously! Beyond the left blue gate, there is a "Missile Tank". Once you obtain this, there are no more items in this area.

Proceed as directed by the arrows and return to Brinstar. Be careful as there are narrow platforms and other difficult sections! At the POINT location, freeze the Rippers to create platforms and proceed.
※ If you get a game over, you can return to the elevator.