Bomb Search

Walkthrough: After stepping off the elevator into Area 1, you'll enter a room drenched in purple everywhere. Nothing will really be accessible here at the moment, so make sure to leave a pin of your map to remind yourself to come back. After that, step down to the Save Station and proceed to the next little area, the one with purple lava and the Chozo Seals. You may notice four orbs this time on the Seal, so be prepared to defeat four Metroids in Area 1. If at any time you bring a Metroid DNA back here, you'll be able to track the location of one of the remaining Metroid and their Vicinity.

Head through the next door using a Charge Beam. There will be another door close by after you enter, but you won't be able to access it without a suit upgrade. Instead, continue moving up and to the right. At one point, you will need to drop down to the bottom. There will be two doors when you do, but you won't want to go in either of them: one is full of nothing but lava, and the other is presently to powerful for you. You come back at some point, but for now, head passed both of them and the passageway and keeping moving up. There will be a few blocks in your way, ones that will also lead to to the Aeion Orb to recharge. Once you reach the very top, head to the right.

By going right, you'll reach a vast and open area. There's plenty to do in here as you will see, but for now, head to the Save Station on your right. Avoid the first door you pass and then drop down to the lower level of the room. Here, you'll find a passageway that leads to the left. Follow it until you reach the next red barrier, using a missile to access the next door. Proceed through the door to find the Bomb.

Missile Expansion: In the same area you obtain the Bomb, place a bomb on the blocks of the floor just before the ramp. This will reveal a hallway underneath. From there, use the bombs to propel Samus up to destroy the block at the top. This is where you'll obtain the upgrade.