Jade Skull[edit]
The first visit to this place requires you to collect a jade skull.
After going through the portal and opening the door ahead, you will encounter a werepanther. When you head outside, there will be several were jaguars, but also some useful items. Head to the top of the structure, and step on the pedistal. This will raise a block within the lava, which will then open the next door. It will also create a summoning stone, but there's a limited time to get it as the stone block will sink into the lava.
Past the door, you should see a ring of turning. Ignore it as it is not useful here. Instead, proceed to either side path until you reach a large room with a stone golem and werejaguars. Look for a passage on the right, which leads to a broken bridge. Drop down.
At the bottom, there is an exit to the right, which leads to water. Push the switch ahead to open a lower section. In this lower section, you can get the jade skull, and press a switch to open the return path.
If you want to cross the bridge, it does lead to a mystic urn, and a switch that reveals a tome of power.
There's nothing else here for now. Obtain the crystal skull if you haven't already, then continue to the Obelisk of the Moon.
Element of Earth[edit]
When you arrive from the Palace of Columns, you are in position to get the Element of Earth. Head up the stairs, to a room where enemies are in the section below. When you drop down yourself, the only path is towards the element of Earth, where there are crushing walls.
These wall traps don't appear to require anything special, simply run forward whenever possible. After the corner, there's a crushing ceiling that requires timing to get past.
Once you have the element of earth, backtrack to the middle of one of the crushing corridors. There's a passage to the middle, which leads to a lift to exit the trap, and return to the main section. This will also stop the crushers as well.
If you have all four elements, you can head to the bridge of stars using either route.