Talk to Kara to travel to Dao. Talk to the man outside the house you are staying at and you will receive a package from Will's grandparents. Neil is in the house next door. The Jeweler Gem is beside the house Neil is in. You can win 2 red jewels by playing the snake panic game. There is another red jewel in the grass next to the kruks.
Travel to the Pyramid. Defeat the monsters and a Dark Space will open up where you can turn into Shadow. Equip the aura and go up the stairs to the right. Use aura at the spot where you see stones leading down. At these spots, Shadow will be able to sink to the levels below so watch out for them. You will sink down into a room that has a red jewel in the left pillar. Sink down again to get to the room below.
You will see another Dark Space and 6 doors. You can also reach this place directly by sinking down from the Dark Space above. Turn into Will and enter the left most door. Use the spin dash to get up the ramp then use it again to use the jump. When you come to a big ramp up, you will have to use Spin Dash down the small ramp nearby then up the big ramp. When you encounter a blue gateway on the ground, go into the door next to it to get the Hieroglyph. Use the blue gate to get back to the entrance. You can place the Hieroglyphs you will find in the room up top. Use Will's father's journal to see the correct order. This one goes first from the left.
Go back below and enter the second door from the left as Shadow. When you see some stones below the floor, you can use his aura to go down. You will find a red jewel at the bottom of the second area. Go back up to the top right of the area and use Aura at the stones near the platform. Grab the Hieroglyph and use the blue portal. This Hieroglyph goes second from the left.
Turn into Will and enter the third door from the left. Use Spin Dash across the jump to get the red jewel. Leave and turn into Shadow then go back into this area. Use Aura to get down the enter the next area. Use the floor plates to control the moving levels in the middle. This will take you all the way down to a Hieroglyph. This one is placed third from the left.
Go back below and enter the furthest door to the right. After defeating a mummy, you will find some stairs down in his sarcophagus. You will find a set of stairs in another sarcophagus leading to the second area. Another sarcophagus stairway will take you to the Hieroglyph. This one is placed sixth from the left.
Go back below and enter the second door from the right as Shadow. Use Aura at the stones down near the pit. Go all the way left and use Aura to go down to a red jewel. Use the blue portal to go back. Use Aura at the stones near the pit again. Go all the way to the left then use Aura again to get to the second area. Make your way down to the Hieroglyph. This one is placed fifth from the left.
Go back below and turn into Will. Enter the third door from the right. Fight through the enemies and enter the second area. At the far right of the top level of the second area, take the stairs down to get a red jewel. Go back up and take the passage right to enter another area. Time your Spin Dash to get over the ramps without getting hurt by the spikes. The Hieroglyph is all the way to the right. When you go in to place the Hieroglyph, the Jackal will show up with Kara. Get out of the line of sight of the statue near you then play Lola's Melody. With him out of the way, you can place the Hieroglyph fourth from the left. A blue portal will appear outside that will take you to the Mummy Queen.
Mummy Queen
She will turn into a bunch of ghosts for a short period of time every time she is hit. She can only be hit while she is in solid form. The ghosts cannot be damaged or killed but they are fairly slow moving. Use the teleportation stones on either side to get up top and use the jump ledge in the middle to get back down. Using those 2 things, it should be easy to avoid her attacks. Eventually, she will start using the ghosts to spin around the room after you. Hit the one solid ghost to return her back to her normal form.
At the Tower of Babel, you can find the last red jewel on the pedestal between the statues. When you try to walk into the door with a barrier on it, the Crystal Ring will fall out of Will's flute onto the ground. Pick it up and equip it to get past the door. You will have to fight all of the guardians again that you have faced throughout the adventure. They should be much easier this time though as you will fight them as Shadow. You can go back to the Dark Space to recover after the first 2 guardians so don't use any herbs on those battles.
Use the elevator of light to go up. Talk to the guardian when you get outside and he will take you up. There is a door that is somewhat difficult to see on the left. After you have defeated all of the guardians, you will come across a spirit next to a Dark Space. The spirit is able to take you back to Dao. This is your last opportunity to save before the final opponent. Go though the door to face Dark Gaia.
Dark Gaia
In the first part of the battle, target the mouth when it is opened to spit out the green slime. Use Aura when it starts raining down around you. After the comet is defeated, Dark Gaia will appear. Bubbles appear from the left and right sides and will damage you if they touch you. Green energy orbs are also fired at you at the same time from both sides. Use aura to dodge the orbs and clear the bubbles. When Dark Gaia prepares to fire the main beam, she will open her mouth. Target the mouth while it is open and be sure to get out of the way of the beam when it fires.