Classified Intel Acquisition | Side Ops and Extra Ops MGS V: Ground Zeroes Guide
Last update: 11 May 2016
You start the mission on a truck. Get out of it as soon as it passes near your target, which is the tower next to the refugee camp. Get to the top of it and use the spotlight. Watch out for the guards heading your direction.
Use the binoculars. You have to locate the target - informant, with whom you have to make contact. After a minute or so, you will notice him in the company of one other guard.
Eliminate the guard who is with the agent and sneak behind your target. A cutscene will show up, after which you will have to head towards the main base and collect the tape from the central guard tower.
Go to the base the same way as in all the other missions. You will not encounter many guards in this mission.
When inside the tower, make sure that you destroy the camera above the entrance, or that you disable the power first. Take the tape from the desk. If you've done your task fast enough, you will notice that the vehicle on which you had begun the mission is parked in the main base. You can get on the back of it and wait (up to 5 minutes) until it leaves the base. Otherwise, leave the base any other way or using the helicopter. To save some time, you can use any vehicle in the base and drive past the border of the map.
To obtain the S rank, you have to rescue the prisoners as well. However, you need a lot of time to complete this mission, so read about the alternative way, to get the S rank. The prisoners once again are located in the cells near the shoreline.
The alternative way - collect 2 tapes and unlock the achievement
The alternative way described here enables you to unlock the "infiltration" achievement (for riding on the truck to and from the base) and to obtain the S rank (provided you don't raise the alarm, use a checkpoint or be late for the truck). You have to do three things: ride on the truck all the way to the inside of the base and sneaking between the building and the wall, make your way to the ladder and climb up to the tower.
Take the tape. This tape is also one of the collectibles - "Agent's Recording". If you are playing on the Hard level, you won't have the basic weapon with you, only the pistol. Unfortunately, it will not be enough to destroy the camera in the tower, so you have to take a gun from an unconscious soldier, or try to collect the tape in such a way that the camera can't spot you. You can also disable the power before entering the tower. Afterwards, you can get back on the truck and wait until it leaves. However, there is one more tape to collect in this mission.
Now You have to go to the lower base (underground) without raising the alarm. There will be a soldier walking around near the generators. Sneak behind him and interrogate him. If you use this action twice, he will drop the second tape. Head back to the truck.