Metroid Prime 2: Echoes/Sky Temple Keys

Sky Temple Grounds
Now it's time to go collecting the keys you need to get to the last Dark energy controller and meet the boss Ing that control it. If you played the previous game you may remember there was a similar section where you had to chase down Chozo artifacts. The first step is to get clues to the locations of the Key Bearers, Luminoth who managed to locate the keys. You get the clues from A-Kul, the one Key Bearer who managed to survive long enough to bring a key to where it's supposed to go.

War Ritual Grounds
Go to the Hall of Eye, which was on the route to Torvus from the Temple Grounds, and use the portal there to get to Base Access, and from there go to the War Ritual Grounds. We where there previously to get an expansion. This time continue through to the next area.

Shrine Access
Follow the Morph Ball tunnel to reach the main area which is guarded by Corrupted Sentreyes, which you may remember from the Abandoned Base, but which you can now destroy with a charged Light beam. There is both a Green door and a Purple door here, but for now we'll just do the Purple one.

Gateway Access
Get past the Darkling Tentacles to the other end of the passage.

Sky Temple Gateway
This is where you'll eventually take a lift to the Sky Temple, but first you need to get the keys. Scan the tops of the pillars to get nine clues, and scan the Luminoth at the base of the tenth Luminoth's (who left the clues) testament. If you're going after 100% scans and have already gotten some keys then you have to be careful to get the clues before placing the keys; once a key has been placed the corresponding clue can no longer be scanned.

Aside from two missing testaments, which we'll get shortly, this should complete the Lore section of the Logbook.

We'll do the keys in order from 1 to 9 which isn't the most efficient order but it will keep things tidy at least. For each key you need to locate the Key Bearer in the light world using the clue, then look for the key itself in the corresponding room in the Dark world.

Central Mining Station
First we look at J-Stl's clue which says, "Noble J-Stl. Lost his soul before a fortress in the scorched land." The scorched land is obviously Agon Wastes and the fortress there is probably the the Space Pirate area there. Sure enough, we've already gotten the J-Stl's Testament in the Central Mining Station on the way out after getting the Light Beam; J-Stl was in the shielded alcove across from the cannons. Optionally, go back there and switch to the Dark visor to see the shadow of something floating just outside the shield. We need to go to the corresponding location in the Dark world.

Battleground (Dark side)
Get to the Dark world; the location we want is Battleground, which, you may remember, was also the location of one of the Dark Agon Temple Keys. You need to enter from the upper passage coming from Doomed Entry. Switch to the Dark Visor and notice the invisible platforms floating around. Hop these in sequence, using a ledge to reach the last one, and hop over to another ledge opposite to where you came in. You'll find a flying shape that's only visible in the Dark Visor, and it's location is exactly where the shadow was in Central Mining Station. Shoot it once to make it visible, get a scan, and keep shooting at it until it breaks open to release the key. This should complete the Reseach section of the Logbook.

Main Reactor
The next clue is for B-Stl which says, "Gallant B-Stl. She lies deep in a fortress of dry land." This clearly refers to the Pirate section of Agon again, but it's a bit more vague. Her scan is a harder to find, and you would only come across it if you came into the Main Reactor through the White door from Ventilation Area A, or if you used the Spider Ball to get out the same way. The shadow is perhaps easier to find since it's floating in the main room of the reactor.

Dark Oasis (Dark side)
Get to Dark Oasis, the Dark version of the Main Reactor. Scan to find a weakened section of rock made from Benzium just as you come in from Oasis Access. Blast it with a Power Bomb to find a pool of poison water. Above the water there are poisonous little particles called Ingstorm which do heavy damage until you get the Light Suit. (We've been avoiding areas with Ingstorm until now for just that reason.) The key isn't visible right away since it's under water, so jump in and search around with the Dark Visor until you find it.

Torvus Lagoon
The next clue is, "Brave S-Dly. Beside the marsh of a raining land she laid her body forever." The raining land is clearly Torvus and is says 'beside' instead of 'in' so it's somewhere on the boundary. The Torvus Lagoon is one of the first places you see when you enter the bog and in fact you should already have the scan from when you first entered. The shadow can be spotted underwater near where you picked up the Missile Expansion.

Poisoned Bog (Dark side)
This is the Dark version of the area, so jump in the water to find the next key.

Catacombs
The next clue is, "Gentle G-Sch. With a Bearerpod he sleeps in a flooded temple." You may remember finding a Luminoth in one of the underwater areas with a lot of Bearer pods, namely the Catacombs. Head down there and you can see the ghost underwater near the Grey door.

Dungeon (Dark side)
In this case there's a portal right in the same room so there's no extra travel to get here. Jump into the pool of poison water and you'll find the path to the key is blocked by a new creature. Get a scan, then force it to move by activating the light beacon above it with the Light Beam. There are two of them so repeat and get the key at the end of the passage. Get out the same way.