Follow Salim on horseback through the rocky outcroppings of the desert until you jump on the first truck. You’ll want to try and kill as many enemies with hand-to- hand combat for a trophy, so unless there is more than one shooting at you don’t pull out your weapon.
Start by taking out the guy on the first truck with melee and then shoot the enemies on the motorcycles from cover. When you’re ready jump back on your horse and move up to the next truck for another melee kill. Enemies will now begin to approach from behind, so make sure you watch your back before jumping back to your horse. Keeping moving forward until you reach the truck with the RPG’s and use them to kill the two trucks with the turrets ahead of you. Quickly jump back to your horse before the truck you’re on blow up and focus your fire on the motorcycles.
As you enter the canyon you will get a scene where you are knocked off your horse, but no worries as Salim will rescue you and you can continue onward. You can continue to take out enemies by jumping on trucks and taking out the enemies for ammo or cover, but when you reach the lead trucks the game will take over. Jump on the lead truck to rescue Sully and then beat on the Brute until you grab the crane and can hop down onto your horse.
After the long cutscene you’ll be in a large open area corner by the sandstorm, perfect for an ambush or to take out enemies with a low field of vision. Head to the right ignoring the two guards walking and head for the guy on the right for a stealth kill and then loop around the back of the truck and walk along its side. You should see a guy heading up a dirt mound, but wait until he stops before getting behind him and stealth killing him. Do NOT run toward the arches, as a guy will see you, and instead back up the way you came.
Run all the way to the other side of the area, keeping far away from the camp. Be careful when you can see the truck and look for the guy walking in a circles on its left. When he turns around, run up to the back of the truck and take cover so that when he walks back you can jump him. There is an armored unit circling the next vehicle, so look down the right side of the truck and when he turns the corner rush up and kill the other guy in front of the crates, grabbing the M32-Hammer. This should give your easy access to the armored guy, who you can take out now.
When you reach the back area you’ll want to avoid the turrets. Use the PAK-80 to take out the normal enemies as you work your way to the right building and then climb it for an RPG to use on the turret. You can now walk to the left side of the map and up the opposite building for the other RPG. Carefully as you make your way to the back of the area, avoiding the snipers and entering the double doors.
Once you enter the building immediately turn left for the Carved Sabaean Face and then continue up the stairs.
Climb the ladder on the right and drop between the weights for the Bronze Sabaean Bull Sculpture and then climb back up again. At the top of the ladder test the lever and then jump to the chandelier and shimmy around for the third treasure, the The Royal Game of Ur .
Return to the lever so you can ride the weights up and then jump to a ledge. Jump to the lower platform to the right and then climb along the wall to get to the beam that points out over the center of the area. Walk along the beam and then jump from chandelier to chandelier to get to the other lever. With both levers pressed you unlock the city and can jump back to the chandeliers and then to the door for a quick way down.