The following settings need to be made to run the game on the Steam Deck: Steps 1-9 maybe optional if you already did this

1. Install the Game and run it once. It will only show a black screen (audio working)
2. Go to Desktop mode and open a terminal window
3. Set the users password with passwd
4. Switch into root user by running sudo su
5. Make the file system writable by running btrfs property set -ts / ro false
6. Initialize the arch linux keyring by running pacman-key --init
7. Fetch the kys for the repositories: pacman-key --populate archlinux
8. Install wine and winetricks: pacman -S wine winetricks
9. Return to the deck user by entering exit
10. Install DirectX using winetricks with

WINEPREFIX=/home/deck/.local/share/Steam/steamapps/compatdata/33350/pfx wine /home/deck/.local/share/Steam/steamapps/common/Anno\ 1404/DirectX/DXSETUP.exe 

11. Create /home/deck/.local/share/Steam/steamapps/common/Anno\ 1404/Engine.ini with the following Content:

<InitFile>
    <DirectXVersion>9</DirectXVersion>
</InitFile>

12. Set the game options on steam to

PROTON_USE_D9VK=1 PROTON_FORCE_LARGE_ADDRESS_AWARE=1 PROTON_NO_D3D11=1 %command% 13. Launch the game