Divinity: Original Sin Enhanced Edition

Go through the pirates' office in Black Bay. Go down the hidden hatch and kill the pirate Pontius (to get to him, go to the room with buttons and press the “bloody switch” in the bushes; for pressing, by the way, they should give you the Push it trophy, but for some reason they didn’t give me -___-).
After the murder, return to the office again and teleport behind the closed door to take the key and open it. Go down to the very bottom, there are a lot of traps there, but you can actually get through everything without taking damage. Once you reach the end, you will need to teleport again, and then you will see a headless zombie and a portal. The zombie head can be picked up from the festive square of Cysila, bring the zombie head, say that Pontius is dead and the zombie will say that he is ready to serve you. You will receive the trophy immediately after this.