Walkthrough: Anathema
Objectives:
The Anathema level provides three possible entry points assuming the role of either of the following individuals: mailman, the delivery boy, and the mafia guard. Unquestionably, the mafia guard is the recommended choice to complete this mission.
Walk up to the door and use the "examine the keyhole" function to determine when the mafia guy is approaching. Eventually, he'll head towards the door for a quick bathroom break. Hide 47 a few meters away so that the mafia guard doesn't see you. Then use your silenced pistol and aim for his head (you can also use the fiberwire if you're feeling really adventurous). Drag his body away from the door, in case the other mafia guard happens to be patrolling in the distance. (Usually, he's by the entrance to the kitchen or by the front entrance where the mailman would enter).
Head to the entrance to the kitchen on the right side of the house. Use the map to determine if the mafia guard has exited the kitchen. Head past the kitchen and wait for the pool area to be clear. At best, only one guard will be in the area. If this happens to be the case, be sure to stay as far away from them and above all ? don't run, or you will be at risk of taking a bullet or two.
Turn right twice until you find the ladder. Climb up to the roof and head to the balcony area. (Depending on how fast you were, the Don may either still be on the balcony or inside). I took a moderate pace, and so the following steps are based upon the Don being inside his office. Wait for the mafia guard to make his exit from his balcony patrol before crossing over to the wooden plank connected from the roof. There may be guards below, so refer to your map before proceeding. Once you're on the balcony, look through the keyhole to determine the position where the Don is standing. When his back is turned, open the door and go shoot him with your pistol. Grab the prison key and his magnum (the shotgun, golf club, and sniper rifle are optional items to pick up) head back in the opposite direction until you are back at the kitchen's back second entrance. (You don't want to use the first door, because the cook will be alerted to your presence and you'll have to get into a firefight.)
Use the key on the iron door. A brief dialogue between Diana and 47 will take place. Now you have two methods of escape?the main entrance or the red sports car which belongs to the Don's brother. You'll find the Don's brother making routine runs from the second floor to the pool area. In the event that you meet him in between his route, take him out to acquire the car keys. (I found it's best to kill him when he's on his way up the steps, using the fiberwire?however you need to be quick and precise, otherwise you may alert the guards and it will be all for naught). If you get the keys, head back to the garage and sit back for a cool cinematic car escape. Otherwise, if you consider this too much trouble, use any means necessary to safely escape via the main entrance.