Shoot out only the lower 2 shot blocks on the side Samus will be climbing. Grab a Beetom and use Morph or a tunnel crawl to pixel align the Beetom 1 pixel deep into the wall (2 or 3 pixels can also work). If morphed, use X-Ray stand up. Shoot to the right (horizontally or diagonally down) to freeze the Beetom. Continue refreezing during the next steps. Grab the other Beetom and stand close, but not too close, to the first. Do a small jump, but not too low, and do an aim-up shot the frame before Samus lands. This second Beetom needs to be exactly 1 pixel below the first. Refreeze the first before testing the positioning. Jump onto the second Beetom, and run into the wall to clip into it (walking can also work if the Beetom is not too deep). X-Ray climb up 2.5 screens and then fire upwards to clear shot blocks. Continue climbing and finish by walking away from the crumble blocks.

For freezing the second Beetom, only certain jump heights will work. Otherwise the Beetom will skip over the correct position and may be frozen too low (2 pixels below the other Beetom). From a standing position, holding jump for 5, 8, 9, or 12 frames will work; with a crouch jump, holding jump for 5, 6, or 10 frames will work. It is recommended to use a crouch jump, aiming for a 5 or 6 frame jump.

Tunnel crawl with Screw Attack to break the bomb blocks. With a very precise jump and aim down, it is possible to jump deep enough into where the first block was in order to only require a turnaround jump, but it's not easier.

Moving left to right is a bit more tricky to get into the tunnel. Land aiming down approximately 3 pixels inside the leftmost tile. If Samus is too far left she will fall out, too far right and a thorn pushes her out, not aiming down puts her stuck in crouch. Then spinjump right to take a thorn hit and get wedged in the ceiling. Then start the crawl while taking constant thorn damage. Perform one jump per thorn hit. Note that if Samus is hit by the thorn before landing, aiming down is not necessary. Note that a moonfall may be helpful to get into the tunnel. Without moonwalk, a downback can be used instead: fall off with low speed and start a downback right away. (This doesn't always work.)

Moving right to left is a bit easier to get into the tunnel. Land aiming down approximately 3 pixels inside the rightmost tile. If Samus is too far right she will fall out, too far left and a thorn pushes her out, not aiming down puts her stuck in crouch. Then spinjump left to take a thorn hit and get wedged in the ceiling. Then start the crawl while taking constant thorn damage. Perform one jump per thorn hit. Note that if Samus is hit by the thorn before landing, aiming down is not necessary. Note that a downback may be helpful to get into the tunnel: stand fully on the left side of the nearby ledge and run off then start and hold a downback to land in position.

It's a long Tunnel Crawl, so there's a heavy softlock risk.

It's a long Tunnel Crawl, so there's a heavy softlock risk.

Use the Solid Blocks next to the Samus Eater to clip up through the Power Bomb Blocks. The thorns do not cover the entire blocks above. Jump barely only onto the corner to avoid the damage. Carefully jump around the thorns, tunnel crawl slightly to avoid touching the thorns when partial floor clipping. Morph and x-ray can be used instead to setup the clip much easier.

Wedge Samus under the right side slope with either a very clean low jump or tunnel crawl movements. Once deep enough, the clip will happen automatically.