Drive to the marked location to start this mission. After the scene, a NERO helicopter will arrive shortly. Like before, you have to get close and eavesdrop on them on foot. You don’t need to place a tracker on the NERO chopper as well so stay in cover and follow the group into the Cave.
There will be a lone guard by the Cave entrance so throw a rock to distract him and for you to enter the cave. There are bushes inside the cave so use them for cover. Circle around the rock pillar so you can get close to the researcher. Stay there as you eavesdrop on them.
Once the gauge is filled, you don’t have to escape from where you entered. This Cave has another opening so go further inside the cave to find a gap where you can squeeze through. From there, just run back to your Bike to complete the mission.
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