The enemy of my enemy (Light up 6 signaling fires)
To complete the challenge, you need to light up signaling fires. They are usually located not on the ground level, but somewhere above. You need to find a characteristic vessel, usually, there s an exploding pot next to it. In two places, access to the hearth is blocked off by boards, which you need to remove, using rope arrows, or explosives/assault rifle.
In the location, where you have fought two opponents (one of them with a shield), find a wall next to the post driven into the ground, with a flaming vessel on it. From here, you can reveal the hearth with a rope arrow (look a bit up and to the left).
Right past the gate that opens up after the fight, face the gate - there are planks to the right. Fire at them, with an explosive arrow, or use the assault rifle.
Right after you go past the gate that opens after the fight, turn towards the gate - the hearth is on the right.
In the area, where you are attacked for the first time, walk over to the right corner of the location. Then, climb higher and find the vessel, a bit to the right. It explodes after you shoot at it and it lights up the fire.
It is very close to the previous one. While standing in front of the stone gate, look to the right. In the corner, above, you notice an exploding vessel and the hearth. You can approach it also by turning right past the gate.
right past one of the staircases in the destroyed building, up ahead, with a bell above it.