Here it is. Air's Rock. This is, without a shadow of a doubt, the longest, most tedious, and most annoying dungeon in the game, maybe even the whole of Golden Sun. There are three distinct parts to it - getting to Air's Rock, climbing the outside of Air's Rock, and then navigating the inside of Air's Rock. And it takes ages.
The Base of Air's Rock
Right, to begin. Firstly, set Move and Whirlwind to your Psynergy shortcuts, if they aren't already, because you will be using both of these a lot here. Now, go forward and use Whirlwind on the rock here. It'll blow the sand out of the way. Go ahead and keep going north, until you reach a set of rocks in front of a big pink stone, and a lone chest. The chest is a Mimic, which defeating earns you a Lucky Medal (which is useless right now). Head south down the other path and follow this around. Going north to the climbable wall doesn't lead anywhere right now because a pillar at the top prevents you getting past. Go right, and when you reach another T-junction, go right. At the next junction, go up and fire a Whirlwind across to the left - this will clear a path for getting a chest later on. Keep going south to find another Whirlwind stone. Blast away the sand and then go north. Go back around the rock so you can get through the pass you just made. When you reach this Whirlwind stone, use it twice - the first is necessary to get to that big pink stone, but the second will allow you to get a chest. Now use Retreat to get to the beginning of Air's Rock (don't worry, this won't reset the sand).
Go north again, then to the right. Go north to reach the chest, containing a Cookie, then go south and left to reach a different angle of the first stone. Blast away the sand to the left, and go back around. Go through the freshly-created path, and use the Whirlwind stone from this angle to clear a path. If you want, you can go around to the other side of the stone and use it again to blow away some more sand, to reach a chest containing a Smoke Bomb, but I don't think it's worth it.
Anyway, if you follow the new path to the north you'll end up right next to that big pink stone you saw earlier. Go ahead and use Whirlwind on it, and the tornado created is so strong it blows away a whole pile of sand in front of a long ladder. Climb up it to the next area.
Climbing Air's Rock
You can't go right since there's a pillar in the way, so climb up the wall to your left. The wall to your right here doesn't lead anywhere either, so climb up the left again. Drop down the groove here and let the statue blowing whirlwinds blow you across. Drop down the groove here, and down the next one too. Hitch a ride on the passing whirlwinds down here. Shove the pillar off to open up a shortcut, and then head right. Shove this pillar off (this is what was blocking you earlier) and ignore the climbable walls for the mean time. Go down the wall furthest to the right and you'll be back at the base of Air's Rock. This is why you cleared the sand away here earlier - the chest contains the Storm Brand, a very decent weapon for the mean time, so equip it on Felix.
Climb back up. Take the climbable wall on the left here. Work your way up to a ledge. There's a climbable wall leading down to the right, so take that and let the whirlwind blow you across. Ignore both of the grooves and climb up the wall. Shove the pillar off the top (this is what was blocking the other whirlwind statue) and let the next whirlwind carry you across. Climb up to the next area.
Go left, and begin climbing the wall. You have to time your advances here, because the whirlwind statues will blow you off if you don't, and you'll have to start the climbing again. When you reach the top, drop down the groove. Move the pillar onto its metal plate, opening up another shortcut, and climb down the wall. Wait for the statue to blow a whirlwind, then grab the Sleep Bomb from the chest. Stand on the statue, and the next whirlwind will blow you back up to the top. Thoughtful, eh? Now, go to the next area to the right.
Begin climbing this big wall. Go past the first ledge and carry on to the second. Up here, Move the pillar you can reach to the left. Climb back down to the ledge below, then walk across and slide down the groove. Stand on the statue and let it blow you up. Walk across this ledge to the left, and Move the other pillar you couldn't reach before to the left. You can now jump across and slide down the groove, allowing you to use the statue before that was fenced in by rocks. It'll carry you up to the top, where you should climb along the wall to the next area.
If you went the other way this is where you came to a halt. This misty area is endless - if you try to climb up off the top of the screen you'll end up back at the bottom. But, since you came this way, you can move a pillar out of the way. Climb back down (you can go down but not up) and follow the path back to a groove you can take. Go down this one, and the next one, and go back to the climbable wall to your left. Now, scale this up to the top, and back to the misty area.
Up here again, use the big pink stone to clear the mist (you couldn't access it before). Now the mist has cleared, you can start climbing up. But there's another special item you can get! Go back down, until you reach the groove on the first ledge up the long wall. Basically, go back the way you went to move the pillar blocking off the pink stone in the first place. When you get back to the area with the big pink stone, you can climb off the top of the screen and get a Fujin Shield in the next area - equip this to Felix. Head back down...again...so you get back to the pink stone area. Climb up the other side of this wall and you end up on the summit of Air's Rock.
To be completely fair, this would have counted as a dungeon in its own right. But no, you've only done a very small bit of Air's Rock. The interior is ridiculously long. Anyway, go up and use Whirlwind on the pink rock. Lightning will strike and blow a hole in the top of Air's Rock, revealing a way down into the interior.
Air's Rock Interior
You get a Psynergy Stone here to recharge you. That was thoughtful. Go right at the fork since left is a dead end, and follow the path around to a room with the biggest statue yet. You can't do anything or get any chests here yet, so head around the outside of the room and exit through the yellow-dot-marked door at the top.
This is the biggest room in Air's Rock. You can choose two doors here - one's marked blue, the other red. Choose the blue one first. You can't do anything here yet, save shoving a pillar onto a panel. This is important later on, so that's why you did it. Head back to the big room and take the red door.
Follow the path around, and head north. You're faced with an interesting puzzle here - there are Pound Pillars and normal ones. If you stand on any of the Pound pillars and the other one on their side isn't weighted down, the pillar will drop. You need to get across to the other side of this room.
Once you're done, hop over and down the wall. Here, use Whirlwind on the stone to blow away the sand (there's another method of getting across to this side, but a pound pillar ends up in the way of the whirlwind). Hop back across and down the wall again. Go through the new passage and climb up, and at the top use Whirlwind facing downwards to blow away another sand wall. Climb back up and walk around through the new path and down the wall. Here, shove the pillar across on to the brown square, then head back to near the entrance of this room. Keep going south and use the pillar to hop around the corner to the stairs marked with two red dots.
In the next room, go up to the wall and climb down. Climb up the other side and follow the path to a pillar. You'll notice a Combo tablet here but you can't get it yet. Shove the pillar out of the way of the air jet so you can get past. Go up to the top and climb down. Walk across the air jet (it won't blow you off) and move the pillar to the right. Now, walk where the air jet was, but stand one square to the right of it. You'll still be within Move range of the pillar, so use Move to push it back across in front of the other air jet. If you're standing too close the air jet will blow you back, and if you're standing too far away your Psynergy won't reach. Now, the pillar can be used to jump around the rock. Ignore the grey statue and whirlwind stone in here for the mean time.
Down the next wall, push the pillar to the brown panel, then walk around to the left and push this pillar out of the way of the air jet. Use the pillar you pushed before to hop across, and use the groove. Climb up to the left and follow the path (now without the pesky airjet blowing you back) down and out of this room.
You'll be back in the big room again. Hop across and go down the three-blue-dot-marked door. In this room, go down the wall to the whirlwind stone, and use it facing left to blow the bridge through 90 degrees. Climb back up and hop across to the other side of the brdige. Climb around the rocks and head to the left, going around the top. There's another whirlwind stone for you to use, so use it to knock the bridge back around. Go around to where you can get on it, but go across the rope and shove the pillar off to make a shortcut. Now hop across the bridge and go along the ropes to the next door.
The path to the left leads to a chest with an Elixir. Head north after getting it. Follow the path, hopping across various platforms and ropes until you get to a whirlwind stone. Use it to turn another bridge. Go back up, hop across the bridge and across the rope. Go back down and use this whirlwind stone to rotate the bridge again. Hop across, go to the left, hop on a pillar, and across another rope. Follow this path to reach the next door.
Back in the big room again. Jump across and go down the long ladder. Go down the steps at the bottom. This room is purple! Head around the outside and hop across to the centre. The stone in the middle is an infinite Psynergy Stone - you can recharge your party's PP as many times as you like here. When you're recharged, head all the way around and use the stairs at the top of the room. Use the floating platforms to get around the big face in the floor and use Whirlwind on the pink stone. Now, the grey statue below you is now blowing whirlwinds, and you can use this to take the blue path back at the top of Air's Rock. But before you hop on the small statue to take you back up, use the right-most path of platforms to get back outside. Shove the pillar off here to open up another shortcut, then head back inside and use the statue to get back to the top.
At the top here, use Whirlwind on this pink stone, and pretty much every single statue is now blowing whirlwinds. Move the pillar to the left out of the way (on to the brown panel) and then go back around to the right. Use the Whirlwind Statue to get across to the chest, which contains a Vial. Move the pillar to its panel, jump across. From here you can go back to the beginning of the Interior (the yellow-dot door with a Psynergy stone).
Now, if you want that Combo Tablet you saw earlier, take the red path again. The puzzle on the first floor is done already, so you can just hop straight past and down the floor. Now, go back around and shove the pillar out of the way of the airjet again. Go to the seemingly useless pillar in the centre of this floor and move it one square to the right. Head back up to the top of the room using another pillar you moved earlier, and now the whirlwind statue is active, you can use that inaccessible whirlwind stone. Aim it downwards, and it'll carry the "useless" pillar across to the random sliding groove at the start. Go back to where the pillar now is, shove it off onto the brown panel, and hop across to the Combo Tablet. This is Flora, a summon requiring 2 Jupiter and 1 Venus Djinni - it's quite powerful, and can put foes to sleep, but you can't use it yet, since you need another Jupiter Djinni. One's coming up quite soon, so don't worry.
The Blue Path
Now, retrace your steps back to the top of the big room again. Now you can take the blue path. Let the whirlwind statue blow you across this room. The pillar you moved earlier now lets you progress. The next whirlwind statue, as it is, will blow you across to the exit, but there's a useful piece of equipment for Sheba available. Move the statue up two squares from top, and then go on the long platform and let it blow you across. Grab the Clarity Circlet from the chest, equip it on Sheba, then drop down and get back to where the statue is. Move it back down to the bottom and get blown across again. Shove the pillar off the side to open a shortcut, and then go left.
Follow the path around and then hop across the somewhat random platforms, and Move the pillar in the way of the airjet out of the way. Go all the way back around and down the two-blue-dot-marked door. The next room will be familiar, but you don't have to solve any puzzles; just follow the ropes to the next door. Go to the left next, and use the whirlwind stone from both directions - one moves a statue to where it needs to be, another blows away a sand barrier. Go down the ladder behind where the sand was and go up the ladder next to the statue. Let it blow you across and grab the 666 coins (uh oh...) from the chest. Go down the groove, and at the bottom of the room go up the right wall and around the right of the next door - you need to open another shortcut. Shove the pillar off, then return to the door, and go down again.
The right-hand path can't be gotten through yet, due to a whirlwind statue. Go up the left one, getting the Vial along the way, and Move the statue to the right. Now go all the way back, and you can now go up the right-hand path. Enter the door at the top. In this small section, go around to the next door. There are now no more puzzles! Follow the path along the floating platforms to the door in the grey rock.
You're now at the "heart" of Air's Rock - there's an endless void beneath you. Hop across the platforms (they disappear behind you, but you can still get back) to the tablet at the top of the room.
"Wielder of Wind's might, lay you hands upon this stone...we bestow upon thee the power to see the truth unclouded..."
Sheba will touch it, and gain the Psynergy Reveal. Yes. That's what you came here for. That's it. It's actually very useful (as well as being necessary to leave Air's Rock and to finish the game). Take the left-hand path of platforms. Here, you'll see a hexagon of differently-coloured platforms. This is the trademark Reveal hint symbol which will appear anywhere you need to use Reveal. Make sure you look out for these. Anyway, use it and a hidden platform will appear in the middle. Hop across and follow the other platforms to get a Psy Crystal. Head back (using Reveal again) and take the right-hand path. Use Reveal again at the hexagon of platforms and you'll be able to get back to the entrance again. Exit, and now you can use Retreat. Exit Air's Rock, then use Retreat again to get back to the start of the base of Air's Rock. Congratulations - the longest dungeon in the game is now finished. Don't you feel special? On the world map, head south and back to Garoh.