Start the game while connected to Xbox Live and select the "Additional Content" option at the main menu. Choose the "Exclusive Content" option, then login with your Ubisoft account information or create a new account. After the game connects to the Ubisoft servers to verify your information, the message "ACCOUNT LINKING COMPLETE! Thank you for linking your Ubisoft account to your Xbox LIVE Gamertag. Special Machete. Unlock Special Machete" will appear. Press A to unlock the special machete. The message "The exclusive content was successfully unlocked" will then appear. Return to the main menu, select "Options", then select "Game". A new "Machete Type" option will appear. You now have access to the "Homemade" and "Primitive" machetes on the current profile.
If you go for the mission with the blue square on it first, be prepared as you will have to face all your past and present friends for a big showdown. Don't believe them when they tell you that they have your back.
Note: An unpatched version of the game is required. Go up to a thin wall and face directly at the wall, then take out your mortar. Rotate 180 degrees and you will be on the other side of the wall. You can use this glitch to get to several previously-unreachable locations.
When going for the Jackal, after finishing the mission with the blue square on it, you must go to a shack where he is hiding. When you get into the shack he gives you two choices: either take the diamonds or the car battery. If you take the diamonds, he tells you to take them and bribe the commander or take the car battery and fix the explosives. However, if you take the diamonds, be careful with the large hole in the middle. If you drop in, you will not be able to get out.
Enter the main menu and select the map editor. Look around in the "Item List" and look in "Utilities", then "Detail Objects". Look for an item called "Checkpoint", then place the one that has a square sign and is closed off. Look at the sign; it will read "No Trespassing Violators Will Be Shot. Survivors Will Be Shot Again" This is a direct quote that was on the last loading screen before entering the game.
Proceed to the opposite side of the mountain-the eastern side-and look just north of the tree. This tree looks like it is coming out of the mountain. There will be a rock formation next to the mountain that is basically forming a cave. Break the boards blocking entrance into this "cave" to find the golden AK-47 inside.
Go to the southeastern bus station and drive north past the guard station onto the next map. Look around the weapon shop onto the adjacent road to the east. There is a dot on the map. Go to that dot (essentially the southeastern corner of this map) to find an abandoned shack there with a diamond briefcase inside. Next to it is the golden AK-47.
Go to the southwest bus station and drive northwest past the cell. Go in between the two mountains and look on the northern side of the western mountain, nearly directly south of the guard station to the north. Get up this mountain by exploring the western side and moving your way east. Look along the edge of the mountain for a boarded-up cavern. Break the boards and grab the golden AK-47 inside.
Go to the southeast bus station and drive west toward the guard station, but then turn south toward the lake. Go to the lakefront and look for the hut. Continue south from the hut and keep looking at the mountain to your left. After you move through the water around a big rock, look left on the mountainside to find a row of green bushes. Walk through the bushes to find the golden AK-47 in a tight alcove.
Go to the northwestern bus station and drive down between the two mountains northeast of the southern guard station (the mountains just east of the Cattle Xing). Look on the southeastern side of the northern mountain to find a diamond briefcase near a couple of huts.
Go to the southwest bus station and drive up to the TaeMoCo Mine, then search the road that runs east of the TaeMoCo Mine. Nearly directly east from the mine's center is a small abandoned outpost along the road. Look inside for a golden AK-47. Jump through the back window.
Go to the northeast bus station and drive southeast along the road, then past a couple guard stations. Enter the next map from the road furthest to the east, then go past the cell tower and safe house. Follow the river south just past the guard station. Explore the eastern side close to the mountain. You will find a small alcove marked with a red barrel. The Golden AK is directly behind it.
Take the bus to the northeast station and drive through the Crash Site, then west onto the next map section. Go west past Sediko. Connect with the road and follow it west. Continue along this road until you reach the wishbone-like fork at the end. Go left toward the southern side and reach the dot on the map at the end. It is a small outpost, which might include enemies. Find the hang glider on the cliff. Look over the cliff to see the golden AK-47 just below.
After going through the Heart of Darkness, go south from the nearest safe house. As you move east toward the swamp, find a tree appears to have fallen over. It connects the northern and southern sides of the passage. Walk across the tree. Find the golden AK-47 at the top.
Besides from the obvious beeping in your PDA about the diamond case, there are other clues you can use to find your diamond quota. When your map is zoomed into the maximum magnification in a region, there is a small green (or blue) number on the map indicating the number of diamond caches in that zone. This, as well as the lit points of diamond caches you've found, can be used to help you narrow down the areas you need to search.