From the main entrance of Dark Haven, head to the bandit cave to the east. Inside, go up and it's the building to the right.
You are asked to find a cow slave who escaped. He is located at the entrance to the cave that leads to the spectre reagion (blue ping on map)
Time to go look for a bandit who stole gold. Ping again and head to the blue zone in the desert. Find him, slay him.
The guild master wants you to head to Alexandria to kill a priest in the church garden.
Next task is to slay a noble located at Fira Inn. Head to Fira, then west to the inn. He's in front.
You are required to assassinate 4 captains, one after the other. Follow the lead:
- Captain at Ramoria farm
- South entrance of Alexandria
- South of Fira, in the field
- South-east in the desert, blue ping for zone
And that's it. You will get the Ancient Key to enter the Ancient Ruins.