The Free Folk - Complete an Outcast Rescue Mission.
Difficulty : Very Easy
Length: Very Short
You simply need to find and finish an Outcast Rescue Mission, represented by a fist in a shield. There are 24 of these missions across the 2 maps, but they are not available immediately. To unlock the missions, you need to free some slaves. These are found on the map with a single fist, where you need to kill few Uruks guarding some slaves. Once they are dead, an Outcast Rescue Mission should appear on the map.
The Outcast Rescue Mission itself is easy as well. You need to free 3 slaves (more on subsequent missions). You are free to do it how you want, stealthy or combat heavy and you are free to complete or not the Bonus Objective. Get near a slave, and press
.