Lowering a Platform

Step down the stairs. Jump into the pool and dive through the tunnel on the right. Climb out on the other side and grab into the hole. This will lower a floor somewhere. Dive back and climb out of the water. Run up the stairs. (You should have been up the ramp on the left earlier on.) Shoot the chest on the right and pick up the large medipack. Now turn left and shoot the two chests there as well. The left one contains some crossbow ammo and the one ahead contains some revolver shells.

Mechanical Scarab

Now step into the passage on the right. There you'll find two beetles on the ground and between them a row of spike traps. Go to the inventory screen and combine the Mechanical Scarab with the Winding Key to get the Mechanical Scarab With Key. Now use the combined piece while standing on the first beetle. (Be careful you can only use it three times.) The mechanical scarab will trigger all the spikes and it's safe to go through the passage. Pick up the scarab on the other side.

Right Gauntlet

In the next chamber turn left. And run up into the passage. As soon as you step into the chamber with the crypt, the bird blades behind you will be activated. Open the crypt and take out the Right Gauntlet. A skeleton will appear on your right. Destroy it. Now position in front of the bird blades and run through when it's clear. Run back into the previous chamber.

Way to a Big Chamber

Now enter the right passage. On your right is a skeleton. Shoot it. Now run towards the spikes there and use the beetle to deactivate them. (On the left behind the pool, you'll find another spike trap. If you use the mechanical beetle here, you have to climb up into the opening on the right before you come to the second trap row. If you use the beetle there as well, you won't be able to collect a secret.) Run through the passage and collect the beetle on the other side. Enter the chamber on the right. Again, bird blades will be triggered behind you. Open the crypt and collect the blue shotgun ammo. Shoot another skeleton. The bird blades here are a bit higher so you can crawl underneath them. Back outside run up the stairs and down into the next chamber. (There are four passages leading away from that room. The stairs on the left, where you came down. Another passage right of it, some stairs in the middle and a passage on the right.) Open the crypt there to find a small medipack. After that another harpy will appear. Shoot it.

Right Greave

Now enter the passage on the left. (That's between the two stairs. If you use the stairs on the right, you'll get there as well.) In the left corner, you'll find the ground you lowered behind the pool. Drop down. Climb into the alcove to find some crossbow ammo. You'll also find a jump switch on the right wall of the gate. Jump up to activate it. The gate will open and a block will be raised. Shoot the skeleton appearing behind you. Now climb onto the raised block. Turn to face the wall right of the opened gate. Jump over and grab the crevice. Shimmy as far right as you can. Then climb up into the passage. Shoot the chest in the passage and collect the crossbow ammo. Run up the next passage into the chamber with the bird blades. Turn left and open the crypt to find the Right Greave. Shoot the skeleton appearing on your right. Crawl back out under the bird blades. Follow the passage on the right. (The one on the left is where you come up when you've chosen the traps behind the pool earlier on.) Drop down into the chamber.

Pharos Pillar

Run back through the passage near the L shaped hole and enter the open chamber on the left. (Or instead follow the stairs and turn right to get there.) Shoot the chests and collect a large medipack and some crossbow ammo. Open the crypt and collect the Pharos Pillar. Exit the room and turn left to return to the big chamber. Now enter the right passage. Now walk up the stairs and collect the red shotgun ammo. Then use the pharos pillar on the door.

Lara's Double

Enter the big hall. Note the small block on the left. Climb onto the first block and collect the small medipack. A copy of Lara will appear on the other block. Step down from the platform. The copy will stay where she was. (Everything that affects her will affect you as well. So take good care of her. And you should also be careful as Lara will aim at the copy. Be sure you don't shoot yourself. Also watch your energy bar.) The block on the left is now higher. Climb onto it. Jump up and grab the ceiling. Monkey climb to the other side. Run into the corner. Turn around and climb higher up. Run out onto the platform. When you've crossed it halfway, a harpy will appear overhead. Shoot it quickly. It will attack the copy and you'll have a hard time killing it, as you have to be careful not to kill yourself. Turn left and jump over the gap towards the next platform. Either make a running jump or grab the ledge. Turn right and climb into the passage.

Two Jump Switches

Run up to the top. Quickly step towards the opening and shoot the harpy. (In this case, I recommend using a better weapon. Otherwise, the harpy may attack the copy. And it's difficult to get it down there.) Now jump onto the platform in the middle. Turn around and shoot the awakened skeleton. On both sides of the platform are jump switches. (You have to use both of them, but it doesn't matter in which order.)

Left Jump Switch

Make a standing jump towards the left jump switch. The door on the platform behind it will open. You will drop down onto the lower platform. Now shoot another harpy. Jump over to the other platform and climb back up. Jump over to the platform with the open door. Enter the chamber and grab into the hole to collect the Hathor Effigy.

Right Jump Switch

Make a standing jump onto the jump switch on the right. It will open the door on the platform behind. Again, you will drop down. Climb back into the opening in the wall. Run up and return to the platform. Now jump over to the platform on the left. Enter the passage and shoot the skeleton. Grab into the hole to collect the Ornate Handle. Step back out and jump back onto the platform in the middle.

Portal Guardian

Now jump towards the other closed door. Combine the Hathor Effigy and the Ornate Handle. Place the gained Portal Guardian on the staff in front of the door. The door will open. Step inside. Take the skeleton off his feet. Run down the stairs. Shoot the chest and pick up the uzi ammo.

Palace Guards

Enter the throne room. (Movie: Lara will carefully climb down. She will sit on the throne. The gates on both sides will open and two guards will enter the room.) The left guard is the first one to be triggered. He sends blue energy bolts in your direction. Taking them down will cost you a lot of ammo and energy. After you've killed the first one the other will be triggered. I found it easier to ignore them. Enter the chamber behind the left guard. Open the crypt and collect the Left Greave. Now run over to the other side and enter the room there. Open the crypt and collect the Breast Plate. Picking up the last item will open a trapdoor in the throne room. Drop in and follow the passage.