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Symbol (etc etc) Guide
I don't know the location of all of them but here is a small guide. (Going from memory)
Row 1 - Starting "Level Select" Area - 3 symbols:
1 - On a small platform, giving you your first jump ability.
2 - Slide down into the main level select area. There is one on the right side on the platform.
3 - On the way up to the center platform, on the left side, there is one there.
Row 2 - Broken Bridge- 3 symbols
1 - Before dropping down, look left. You'll see the sign in a bundle of rocks.
2 - At those rocks, look toward the back of the area. You'll see a bunch of sand falling from a cliff... head in that direction. There is a small alcove somewhat hidden by the sand falling. One of the symbols is in there.
3 - On the other side of the bridge, you'll see more sand falling, there is a ledge up ahead with one on there. To get it easily, if you have all symbols up to this point, you can stand on the rocks near, make sure you have released the cloth near them, shout to get them to boost you up and make your way to that spot.
Row 3 - The Dunes - 4 symbols (this one is a little harder to remember...)
1 - It's somewhere a long the "normal" that of things... sorry my memory eludes me.
2 - There is a decently sized collection of buildings off into the left side of the map. If you notice a triangular piece of building in the ground near the beginning left, you aren't too far off. Just follow the "arrow" up the dunes and you'll see the buildings there.
3 - There is a circular platform just before the end area. Stand there until a star/symbol hits.
4 - On the left side of the final platform, run around the left of the stairs, follow it around until you get this one.
Mirage Trophy - Once you begin this area, get the cloth guy to come out, then run off forward/right. It's probably one of the most right places in this area. You'll see a few pieces of rubble and a yellow flower. Go up to it and touch it or sing.
Row 4 - Sunken City
1 - Not too far from the beginning, there is a long platform going "straight" IN THE MIDDLE RIGHT AFTER THE BIG CLIFF PILLAR. Hop on before you lose your chance. There is a symbol on here.
2 - At the end of the first section, you reach a tunnel with sand at the end... you FLY out there. You must fly to the right (straight to camera's perspective) and there is a high up ledge with a symbol there. You can use a couple groups of cloth + jumping to get up there.
3 - After you move on from that section, you will notice a large center piece cliff. Go around it to the left, stay close to it though. Slide past it, and then stay left after you pass it, hugging the next cliff. You'll see a rock that juts out. A cloth creature will carry you across the gap, and the third and final symbol of this area is here.
Row 5 (First row on other side) - The Cave ("Underwater City")
1 - In the first few minutes you'll notice broken "tube" or "tunnel" like structures. There is a set of them where you'll see one propped up by another. Fly to the tube that's propped up, turn around and fly in. There is a symbol there.
2 - Next section has a bunch of "sea weed." There is a "T" structure (when looked at from a top/down perspective) jump and fly into that. There is one right at the cross section of the T.
3 - This is a bottomless pit section. Lots of jelly fish looking things. Go as high up as you can. There is one up top on the highest jelly fish.
4 - This one is near the final slope at the end where those meanies fly around. You'll see a bunch of broken stuff on the left side and a pillar. It's behind all of that near the path.
Row 6 (Second row on other side) - The Tower
1 through 3 - These are all easy to find. Raising the "water" will make them even easier to get.
4 - There is a "barred" off area on the perimeter of the area. You'll see the little glowing sign behind small pillars looking like it's barred off. Jump/swim toward it. There is nothing blocking it on the sides, grab it.