Mafia II: Definitive Edition

Story related and cannot be missed. 

It is recommended to do this in chapter 15 "Per Aspera Ad Astra".

Pick up the phone and leave the house. You will be given a surprising ride and will then be dropped off at the side of the road with one last chance to clear the road. Steal a car, equip yourself with good weapons  and head to the observatory where some fierce firefights await. As soon as it starts, switch to a submachine gun immediately; load through and aim for the top of the stairs. Ideally, you should catch the entire host of enemies before they get dangerously close to you. With your weapon at the ready, go around the building on the right-hand side. Again and again, small groups of opponents come up against you but you make short work of them. As soon as you enter the building, watch out for the shooter on the skylight. In addition, opponents are lurking on the left of the first flight of stairs. Fight your way to the roof and keep the gangsters at a distance as far as possible. You reach the telescope room and shoot yourself down the stairs. While there are plenty of bad guys in the museum rooms, they also have more than enough cover to deal with them. Stay behind the rows of chairs and avoid being flanked. Also watch out for supplies through the doors on the side. It's a good idea to sprint all the way out for a quiet moment and take cover behind one of the desks. From there it shouldn't be a problem to finish off all opponents and ultimately Carlo as well. Then you leave the building with Joe. Congratulations you got the torphy!,