Apparently, the control room that housed the switch which activates the time lock was not in Abu Simbel. Thus, Sam travels further into Egypt to find it, where he does so and then is extracted.
As you exit the cave, the battles shouldn’t be too hard. Use the sniper rifle to take out the Reptiloids and Werebulls, rocket launcher for Scrapjacks, and the lasergun or assault rifle for anything else. Use the lasergun when you encounter a large group of Reptiloids in the area with the Jetpack.
After acquiring the jetpack, fly over back to the starting area and over the dam. From there, fly to the end of that area inside building, and collect a keycard inside it. Then, proceed back to the highway in the previous area, and use the keycard on the pipe system and proceed to slide down in it.
Then, after some walking, you should encounter Kamikazes, Kleers and some Major Bio-mechanoids. Use the same tactic as before; lasergun for the Kleers, assault rifle for the Kamikazes and rocket launcher or Devastator for the Bio-mechanoids. Then, you should enter the final area, which houses a lot of Kleers, Kamikazes, Scrapjacks, Major Bio-mechanoids and some Khnums. Use the same tactic and the Devastator (or SBC Cannon) against the Khnums. Then, after killing all of the enemies, proceed to the underground temple.
When the boss fight starts afterwards, take out the incoming Kleers and Kamikazes first, then proceed to lay down C-4s on the ground and detonate them when the Scrapjack Boss walks over them. Alternatively, sprint to him after he’s done shooting, throw and attach a C-4 onto his chest, sprint away, detonate and wait until his melee attack is over. You can also use your cannonballs, Devastator shells and rockets on him first.
Battles in the final areas can be much easier if you lure crowds of your enemies (Kamikazes, Kleers, Werebulls, Khnums, etc.) back to the starting dam. They can't climb up the slope, so you can safely shoot them from distance. However, beware: Kleers, when attacking in mass, can throw each other to the air and reach you.
The key to the underground temple is on a table in the farthest part of the ruin.
- Try to save sniper rounds to pick off Arachnoids, Werebulls and Reptiloids; you will encounter a lot of them.
- Don’t be afraid to waste your ammo towards the final area, as it’ll be the last time you’ll be using them.
- When using the jetpack, make sure to fly on high ground and keep an eye so that it doesn’t overheat!
- Enemies can be drowned in the small pond near the starting point; especially useful against the Werebulls.
- At the starting area, dive into the small pool all the way down to find a minigun.
- As you exit the starting cave, look to your right, you will notice an enormous rock pillar. After acquiring the jetpack, fly over behind it and walk/fly up to the top to discover a cannon with some cannonballs.
- In the area with the jetpack, behind some rocks over the small ruined temple lie some items.
- At the first highway you see with the Scrapjack, Arachnoid and/or Reptiloid on it, the leftmost/farthest end has a locked gate, and a panel to the left. After acquiring the keycard, use the panel to open the gate and collect some supplies.
- After sliding down the pipe and losing the jetpack, when you hit the ground, shoot the Kamikaze running right to left on the top of the first bridge before he teleports out. Then continue towards the second bridge, where you will trigger the "Revenge of the Kamikaze" secret and get attacked by several more Kamikazes.
- At the end of the level, before entering the temple with the control room (and starting the Scrapjack Boss fight), go all the way to the end of the valley behind the temple. Inside some bushes is some armor. (You can do this after you’ve started the final boss fight as well, but it’s easier to do so before.)
- At the final area, in the center, you’ll be between two pylons with rubble in front of them. Jump on the rumble of either of the pylons, if you can’t jump to the left, jump to the right. If you can’t jump on the right, jump to the left. Repeat the process until you have reached the top and press a switch. Repeat this sequence for the opposite pylon and a teleporter will appear between them on the ground, which will teleport you back to the starting area, where an enormous Kamikaze will be standing in front of you, then rapidly charge at you. Kill him to register the secret.