Tomb Raider Underworld Strategy Guide 31: Southern Mexico, Part 11
You will then need to go left, and find a ledge very close to the wall. Jump to it, and shimmy right. Go all the way, and jump to the next one, and the one above it. Shimmy right and backwards jump when you get to the end. Flip off the pole to another pole, and Lara’s weight, light as it is, will bring the lever down, opening the gate.
You will find yourself in a place which requires to ledges to jump up, and you can slide down to the next area. Follow the hall and take a right, another right, and then a left. You will find the Sixth Treasure.
Run back to where you slid in from, and you might notice a pole just hanging on the wall. You will need to chimney jump to get to it. When the pole comes down, a door will open, and you can slide out.
From here, you will be at where you came in. I would suggest running to the altar and use the gem key to open the doors, the ones that slammed on you when you entered this area.
Run back to the Mayan trap room, and the headless statue that you need to drop the head on will be right there. Go ahead and move it into position, and you will notice that there is another headless statue, located where you originally entered the room, as lost its footings. Go ahead and move that one closer to the pool, and some doors will open.
There are in the lower areas in the corner. Go on and take the motor cycle and go down there. Go down three flights of stairs, and then get off the bike. You will soon see a large open area. What you need to do is take out the thrall there, and then go up the ramp.
Jump up to the ledge in a close-quartered area. Jump up one more, and then shimmy left around the corner. Jump up one more, and then backwards jump to a ledge where you can stand. From here, you can shoot some weak supports that will drop a pillar down.
This pillar will now be in a very prime location. Release yourself down, and then jump to the pillar and then the bridge. At the end there will be a puzzle to solve. This one is a lot like the heads at Croft Manor, but a little harder. First, I would highly suggest moving all first three tiles down, and moving the tail all the way to the left where it belongs. Move the head all the way right, and move the second tile from the right down. Move the third tile where the second tile was, and move the head up, and move it all the way to the right. I don’t think I have to tell you where to put the last piece.