Rewards: Pounds: 1160 (+250), EXP: 500 (+250), Schematic: Maximum Dracula Schematic
Challenges: 1. Do not use ranged weapons to kill the decoys. 2. Escape the Alhambra in less than 90 seconds.
Enter the garden, move past the fountain and double assassinate the two Blighters, then take the mask from one of them. This allows you to move close to the Usher. Slowly walk towards the entrance with the group and a cutscene will play. Afterwards you'll be inside the venue.
Head up the stairs to your left, then into the next room. Take the stairs on the right side up to reach the vantage point. You have to kill several decoys first, preferably without ranged weapons. The waitress can (unknowingly) help you with this; she's on the floor below you. Speak to her and Jacob will automatically put a poisonous substance in the drinks she's serving. Follow her around to watch her poison the decoys. Alternatively you can also just kill the decoys. As long as you don't use ranged weapons you'll still complete the optional objective.
When you've killed three decoys, move to the left of the stage and preferably ignore the last decoy here for now. Look for the purple indicator for the unique kill oportunity and free the machinist so he can lower the rafter. You can now kill the last decoy. Climb the stage walls, then move onto the rafter and cut the rope. Afterwards, quickly head to the other side of the room, rope launch to the second floor, move through the open door and hop down on the other side. Quickly make your way outside from here.