Far Cry 3 Ambush takes place after This Knife’s For You in the main story quest. At the end of the previous quest were asked to help save Rakyat’s warriors.
After leaving the temple you will need to seek out and speak with the Rakyat leader that is leading ambush attack.
Go talk to the Rakyat Leader.
The Rakyat Leader can be found at the church in town northeast from Citra’s Temple. After short cutscene you will need to block the incoming Vaas convoy.
Place the explosives on the fuel truck.
In order to stop the Vaas convoy you need to place the explosives on the fuel truck you can find near the Church. As soon as you leave Church turn right and approach the left side of nearby fuel truck. While you approach it you will notice yellow spot on the left side where you need to place the explosives.
Reach the top of the water tower before the convoy comes within sight of the village.
As soon as you place the explosives, you will need to climb up at the water tower at south west town position. You only have 45 seconds to reach the top of the tower so move quickly. As soon as you plant c4 explosive turn left and you will see the water tower in distance. Sprint to it and proceed to the top.
Wait at the top of the water tower for the convoy to get ambushed.
When you reach the top of the tower you will find a sniper rifle and some ammo. Get ready to put the rifle to good use.
Stay inside the water tower until the convoy is ambushed
When the fuel truck explodes the enemies will come out of their cars. Begin taking them out with your rifle, but beware that the privateers you miss will probably notice your position and start firing at you. Keep fire on the privateers that hold their position, they are easier to hit than the ones that are moving.
Climb aboard the cargo truck before the convoy gets too far away!
The cargo truck can be found at the end of the zipline that leads from Water tower you are in. Jump on it and get inside of the truck. A time limit will appear on screen, you will need to reach the next checkpoint before time runs out.
Eliminate the remaining privateers.
Upon reaching the vehicle the privateers are protecting you will find a couple of pirates defending its position. You can drive the vehicle over them or get out and kill them the old fashioned way.
Save the prisoners inside the convoy truck.
Open the rear door of the vehicle, but don’t be surprised if its contents are a little different than what you expected….