First, go to the Don's camp. Talk to Cormac and ask him about the temple behind(under) the camp. He will guess that there are something there. Talk to him again after you retrieve the Hammer of the Titan Lord.
Don Estaban will not give any help, but he will offer you a Strength Potion (+5 Strength Permanently)
Find the entrance near the Dancer and left of the big gold pile.
Kill three ghouls with long-range weapon by using the geographical advantage. (Step onto a piece of rock so that they can't hit you.)
Then, break the blue magic barrier as usual by using the scroll or the Rune.
You will first see two skeleton warriors, then kill a bunch of Skeletons and two undead warriors You will see some broken rocks on your right, which combines into a small platform. On your left is a smaller platform in similar shape. An altar was placed in your front. You need to take the bust and activate the altars in order to open the door and retrieve the Hammer of the Titan Lord.
Step up the stone platform and take the Stone Plate, then use the levitatation spell to get to the platform on the right.
Kill two skeleton warriors there. You will see three doors.The door on the left and in the middle could be broken by a pickaxe. The door on the left-hand side contains a skeleton warrior. The door in the middle have a switch that you have to press it to open the door on the right-hand side. You will see five sarcophagi in the room.
Let's open it clockwisely starting from the left.
The first sarcophagus (marked by 1) contains a skeleton warrior.
The second sarcophagus (marked by 2) also contains a skeleton warrior.
The fifth sarcophagus (marked by 5) is again a skeleton warrior.
Then go back to the main room (the room that you just enter this temple) and start going to the left-hand side of the temple.
You will see two Skeletons and again with three stone doors.
You will see a stone table in the end of the corridor, take away the Stone Plate and an Amulet.
Break through the right-hand side door. The room contains a skeleton warrior.
Then break through the door on the left. You will see a switch that you need to press in order to open the door in the middle.
The door in the middle have a trap that was made by 12 spike traps. You have two methods to get to the end of the room:
1. Observe the pattens of the spikes. You will see not all spikes rise up together. Some of them will close and they will rise up in a second or so.
First, step on I and II. Then step on III when the second set of spikes raised up. Then step on IV. Wait and step on V when the spike disappears. At last, step on VI and get to the other side of the room.
2. Use levitation spell
This requires a bit of luck and precise timing. When you see the trap of number V have raised, use levitation to go there. By the time you get there it should have been closed. Then walk out from the trap quickly. Maybe someone could just levitate through the traps but I can't do it.
Open the sarcophagus and you will see a skeleton warrior. Kill it in order to retreive the bust from its body. Pull the ring of the right-hand side of the wall to deactivate the traps AFTER you kill the skeleton warrior. If you pull down the ring before you kill the skeleton, then you have to pull the ring again.
Get back to the main room and place the lizard mage bust on the altar in order to open the big door. Inside you will find two Undead beasts. Kill them but don't engage the Shadow Lord.
After killing the beast, you could engage the Shadow Lord. But you could not deal any damage to it because it is immortal. Kill it by running into the opposite side of the Shadow Lord. Hopefully he will follow you. Press the button on the walls (there are totally three of them and you could press anyone of them) to activate the trap in the centre and burn the Shadow Lord into ashes. Try again if you failed to kill it.
Take the Hammer of the Titan Lord and gain 1000 XP and teleport (or walk) back to the Bandit Camp.
Talk to Cormac to gain XP and Fincher to gain a little experience.