You've just entered the Chozo Ruins, a massive temple structure in the western expanse of Chozodia. Drop down into the giant darkened room below and try to avoid being spotted by the Zebesians ahead. Don't worry if they spot you, just drop down to the very bottom of the room and crawl through the narrow tunnel in the left corner. Run through the next corridor blowing down walls and blocks in your way, and don't stop if you're being chased.
Beyond this corridor you'll find a small chamber with an alcove in the ceiling, jump up there and hide in the shadows if Zebesians are hot on your six. Stay there and watch as a stupid Zebesian runs straight through the room without seeing you. Go left to enter the safe confines of a Save Room, so be sure to save before moving on. Our new target is a room way up in the northern expanse of Chozodia almost directly above where you are now.
Along the way you'll find ancient hallways littered with patrolling Zebesians, so the stealth game isn't over yet. Cross the following room adjacent to the Save Room to discover a huge room filled with security spotlights. You can try climbing up the platforms to reach the upper-right door in here but you'll risk being spotted by sneaky Zebesians. See the shaft leading skyward near the door? It'll be much easier if you Wall Jump up it to reach the door safely, but you'll have to wait for the spotlight patrolling the shaft to hover down to the ground before climbing up.
If you ever unluckily set off an alarm, just run. Descend the next shaft and go right. Trek through the next corridor (shooting out the blocks below each outcropping if you're being chased) and climb up the shaft at the far end before heading right through the open door. In this following room your path will be blocked by a shutter above if you're being chased, there's not much you can do except stun the Zebesians coming through the door and backtrack to a safer area. So now you'll know the importance of stealth in this area. Once the shutter's open, go left and ascend the next shaft before heading right.
You'll now find yourself in yet another tall shaft, but this one has a twist. Small eyes moving up and down the left wall emit alarm beams across the shaft - trigger one of these and Zebesians come running (and to top if off the darn eyes will fire projectiles at you!). Notice that the lasers can't penetrate the blocks, especially the blue areas. These blue areas act as a sanctuary, you can hide in them and the lasers won't see you.
Very carefully climb up the shaft while hiding in the blue areas, but be warned that as you hang off the edge of the larger blocks the lasers can see Samus' foot hanging off the edge, so time it well when you climb up onto the blocks. Watch out for more lasers above, if you trigger one just keep going. Go left at the apex of the shaft to find a corridor where Zebesians wander about below a thin platform.
Your only way forward is through the narrow tunnel above the platform, so crawl in and go left. As you touch the platform the blocks will slowly begin to crumble, and you don't want to fall down into the Zebesian's grasp. Keep crawling and quickly shoot out the three blocks barring your path along the way. Walk over to the small platform in the floor ahead to fall through down a long shaft. Unfortunately a Zebesian hiding within the right wall will see you and set the alarm off. Fall down to the bottom and run into the next room on the left.
Don't hide in the shadows of the alcove in the next room, just keep going through as if you do hide there a Zebesian will go into the room on the left before coming back through a narrow tunnel right in front of the alcove. In the next room you'll find a blatant dead-end with a door leading back right above the one you entered the room via. Quickly shoot the dead-end wall to break it open and run into the next room.
As fast as you can climb up the following shaft and go right at the top. Don't bother hiding in the alcove of the next room either as a Zebesian will keep walking in and out of the room. Shoot open the blocks ahead covering the narrow opening and crawl through. Zip up the next shaft, at the top you'll see a strange statue above holding a Power Bomb - but you can't reach it from here.
Run into the next room to find yourself in a closed-off alcove. Go up against the wall to fall through crumbling blocks below, you'll now be safe from the annoying Zebesians. Climb up the shaft to find the shutter blocking the way open up. On the left wall behind you a door appears leading to a Save Room, so it's a good idea to save now, especially if you're playing on Hard mode. Walk into the next room to find the statue inside, but the Power Bomb's gone!
Quickly move on and climb up the room to spot a cheeky Zebesian walking away with it! You won't get a chance to grab your first Power Bomb until later, so follow the Zebesian right for now. Descend the next shaft very carefully to avoid the laser beams moving up and down, remember to stay in the blue alcoves to remain hidden. At the base of the shaft crawl through the narrow tunnel to find another shaft leading skyward, also patrolled by a laser eye. Like before take your time and watch the movements of the single laser carefully as you ascend the shaft.
At the apex go right to find yourself at the head of a long corridor filled with patrolling Zebesians. This corridor is the trickiest area to sneak through without being spotted, even Sam Fisher would have a hard time (well, that's probably exaggerating it just a bit). The first Pirate is running back and forth on a floating platform just ahead, very slowly move to the right until you can see the edge of the platform.
Wait for the creature to turn its back and patter over to the right before running out. Run underneath the platform and the stupid thing won't see you. Another Zebesian patrols a platform ahead, move slowly right until you can see him on the edge of the screen. Wait for the Zebesian above you to walk over to the left side of his platform at the same time the second one wanders over to the right side of the next platform before moving. You'll need to wait for them to both move away so neither one sees you. Quickly crawl under the next platform and slowly move right.
Stay within the shadows and crawl right until you see the next Zebesian just ahead. This one's walking along the floor, so you'll need to jump up on the floating platform above to avoid detection. Once again wait for both visible Zebesians to turn their backs and walk away from each other at the same time before jumping up to the platform. You'll need to be extremely fast to avoid detection here, but if they do see you just keep running right.
If you successfully manage to get on top of the platform without them seeing you, wait for the Zebesian below to walk left then quickly drop down - don't jump - and run right. Quickly zip through the door and hopefully the Zebesian standing right above it doesn't see you. If you are spotted in that corridor you'll have a hard time shaking them off, but it is possible so don't give up.
The following room is a giant shaft leading up and down, climb up until you spot a narrow opening in the left wall. If you're being chased, try to Wall Jump up the shaft above to escape from the Zebesians. If they follow you, go through the narrow opening into a dark corridor, then stun the Zebesian following you and re-enter the shaft. Before the Zebesian crawls out of the opening Wall Jump up the shaft and you could possibly escape from your pursuer but it will be tricky.
If you can't get away from it keep trying this trick, as I've tested it and it often works for me. Another way to escape is to keep crawling left through the tunnel - don't stop or be intimidated by the three foes crawling along after you. As you emerge quickly run left into the next chamber then back inside the darkened hallway again.
Stun the Zebesian following you back inside then quickly crawl into the small tunnel and crawl to the right. If you're fast enuogh by the time you reach the far end the alarm should tone down and you'll be clear. Keep going right and re-enter the tall shaft to make the Zebesian following you disappear, then go back inside and carry on.
Meanwhile back at the ranch, crawl through the darkened tunnel where two the Zebesians hang out in small alcoves above and head through the left door at the end. Climb up the next empty shaft and go left.
Walk down the narrow corridor you'll find to discover a huge chamber in which your exit lies up in the top-right corner. Keep going along the floor to the left, but watch out for the Zebesians up in the alcoves in the ceiling. Wait for each one to walk right up over to the wall before running past. At the left end you'll discover a narrow shaft filled with floating blocks. Climb up here and head right over the narrow platform bridging the gap.
Jump up over the gap on the right end and pass beyond the open shutter to locate another Save Room. You can now breathe a sigh of relief, the hide-and-seek game is finally over. You'll definitely want to save your game here before moving on. Go right to find a sudden change in the atmosphere, the deep dangerous musical theme changes to a soft and heavenly tune. You can't enter the watery part of this room for now, so instead climb up the narrow shaft ahead.
At the top cross the empty corridor and go through the open door at the end. You must be thinking by now that the Chozo have left something behind here of significant importance, you're about to find out what it is.
Upon entering this room that you've been gunning for ever since entering the Mothership, you'll witness a cutscene of Samus recalling early memories of the first time she visited this place. You'll see a young Samus hand-in-hand with a Chozo Elder admiring a giant engraving/painting of a Chozo Warrior carved into the wall of a huge chamber. So it looks like this is where the Chozo first trained Samus since rescuing her from the ruins of the earth colony where she lost her parents.
The game shows a close-up of Samus' innocent young face before returning to the face of Samus today. She'll then look up resolutely and with an extremely determined look. So what's going on now? The game returns with Samus standing in front of the huge engraving set in the wall surrounded by paintings, which appears to resemble a Chozo Warrior clad in armor bearing a strong resemblance to Samus' Power Suit.
The four small orbs surrounding the statue will then abruptly glow and fire blue energy bolts into the round mirror within the statue's grasp. As a test of strength and will, you'll now have to battle the engraving itself! There's no choice but to fight it, refer back to the bosses guide to pass this test.
Once you've struck the mirror a fourth time the blue apparition-like creature will return to the wall as the final orb is set into the wall. Walk over to the center of the room and watch as the mirror-image of Samus appears again. But this time her image shimmers to reveal a glorious sight - the Varia Suit! You'll then witness a short cutscene showing energy flowing up over Samus' body, before the mirror restores her entire Power Suit!
Now that's more like it! Not only do you get your suit back, but it's been upgraded and can interface with all three Unknown Items you picked up earlier! The game reveals them as the Plasma Beam, Space Jump and Gravity Suit, all of which you'll receive right then and there, before the game gives you the final word - you've recovered Samus' fully charged Power Suit. The Chozo are such good people.
Enjoy the beefed up Brinstar theme that begins playing, and give the Space Jump a try to reach the exit up above on the right. Roll through the narrow tunnel there and drop down through crumbling blocks as a massive column falls down to block the entrance to the statue's room. As you fall back down into the room outside, two Zebesians will charge forward to attack. You know what to do. The Plasma Beam works wonders against them, and so does the Screw Attack. No more hiding from these creatures now.