In order to begin this mission, speak with Zio who is waiting for you in the Frontier woods.
After a short talk, head onto the road on the left and hide inside the carriage.
That way you will get behind the palisade.
Optional objective: Do not kill any guards.
After you leave your cover, head between the bushes to the men marked orange. You need to eavesdrop on their conversation.
In order to do that, follow them while making sure the don't notice you. Also look out for one of the guards patrolling the area. The best hideout are bushes and haystacks.
After they head onto the upper level, climb the nearby ladder and jump down from the roof into the haystack below.
Soon enough your main target - in the form of a map held inside the nearby tent - will be marked with a green dot.
In order to get it, sneak into the bushes on the left and knock out the nearby guard bare-handed. Only if you don't kill any guards will you complete the additional objective. After the man falls to the ground, steal the map by holding down the interaction button.
Optional objective: Sabotage cannon - 2.
Optional objective: Completed all the constraints in one playthrough.
Now you can leave the camp and end the mission or sabotage 2 s. To destroy the first one, head into the bushes nearby the guard on the wall and wait for him to turn his back on you.
He will give you a couple seconds to approach and stun him.
After taking care of him, approach the cannon and hold down the interaction button to render it useless.
To reach the second target, you should lower yourself behind the wall by the cannon and the palisade edge and walk to the cannon.
A single guard will be waiting there. Wait behind the corner for the man to turn around, sabotage the cannon and quickly hide in the bushes on the left.
From there you can stun the enemy patrolling the road.
With the area clear, sneak to the end of the bushes growing by the wall. On the right you should see a house. Go round it from the right and jump into a hay cart standing by the palisade. That way you will find yourself in the place from where you eavesdropped on the two men some time ago.
Kill the patrolling soldier from here and afterwards head onto the wall above the gate.
On the other side of the roof you will find a couple wooden planks which you can climb onto.
Climb them and jump onto the roof on the right.
You will now have to jump far to the right, to a place not watched by the guards.
After landing safely, quickly run behind the palisade and immediately turn to the woods on the right. You need to leave the red zone before the soldiers can get an idea of what they saw.
That way you will end the mission.