Killing Floor 2 – 'Unlock the Castle Volter's trophy room'

All the valves you need to interact with for getting the seasonal mission.
it seems you can’t enter the trophy room in endless mode, I uploaded a HOE playthrough of this map with opening the trophy room and entering it, you can watch it here: https://youtu.be/DC2QgoWMRPE

Game: Killing Floor 2
Developer: Tripwire Interactive

Steam Page: https://store.steampowered.com/app/232090/Killing_Floor_2/

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