As the name of the chapter implies, the Kreisau resistances headquarters are under attack.
Blazkowiczs old friend, Frau Engel, discover where the resistance members hide and attacked them while Blazkowicz was in London. Now its up to him to save whats left of their home.
There are only two collectibles in Chapter 15, but you may overlook them in the heat of the battle.
Check the Wolfenstein: The New Order guide below to learn about their location.
Chapter 15 Mission Details
So, you came back. Took Anya and the others with you. Well, Im still standing. As long as I do, theres no place in this fucked up world you can hide.
Gotta get inside first, save anyone whos still in there.
Wolfenstein: The New Order Chapter 15 Collectibles Guide
Gold (Gold Shoehorn)
Deal with the enemies that are outside and then get in when Max opens the hatch for you. When you get inside you have the chance to stealth kill a commander, but only if youre quick enough or the other soldiers will spot you.
Head upstairs and go to Klaus room, which is the first room on the right. The Gold collectible is on the table to your left.
Letter (Maxs Letter)
Now head inside the adjacent room, Maxs room.
The Letter collectible is next to the bed, on the floor.
It is also the last Letter in the game, and if you acquired the other 9 you will unlock the achievement / trophy named The lives of others.