


I found I got a slightly higher framerate from using GE-Proton (measured using the steam decks built in performance overlay).
Didn't try online as the anticheat doesn't support Linux

The game didn't close after playing.
Easy anti cheat didn't work.

Just some minor issues with Ubisoft Connect Overlay showing Notifications that I couldn't easily remove.
If you want to remove Ubisoft Connect Notifications just go to the main menu select Ubisoft Club - Settings - Disable in-game notifications
The game ran at a perfect 35 - 45 FPS on Medium to High settings no graphical degredations no audio issues no nothing the only issue I had was with Ubisoft Connect's Overlay it would give me notifications saying I couldn't run the game well enough with my hardware and I couldn't remove these notifications easily.
To remove the notifications I exited to the main menu of the game selected Ubisoft Club then settings and then disabled the in-game notifications and the issue was resolved.
I am using an LCD Steam Deck with 1TB SSD

If you have it on Ubisoft Connect like I do, this is how I installed it using Lutris:
- Go to Desktop Mode
- Install Lutris
- Using Lutris, install ubisoft connect launcher
- Run the ubisoft launcher, log in, and install Watch Dogs 2
- Launch game until you start playing just to check everything is ok and then quit the game
- Add ubisoft launcher to steam, go to its settings and in Compatibility set it to use Proton Experimental
- Go to game mode, launch ubisoft launcher from game mode, click on watch dogs 2 and click install. It's already installed and just need to locate files.
- You can now play the game from game mode.
If you start the game and you have pop ups from ubisoft saying you don't have enough RAM or whatever, that's the launcher's overlay. To turn it off:
- with a keyboard, press Shift + F12 to open the Ubisoft overlay
- you can then click to close those pop ups and go into the ubisoft overlay settings (gear icon on the left) and turn off all notifications.
- if you don't have a keyboard, you can map other buttons to Shift and F12 to access the overlay (eg. L4 and R4)
I only had to turn off the overlay notifications the first time I launched the game and had no problems ever since. It runs well on high settings but turning it down to medium will get you more FPS.

STEAM_COMPAT_DATA_PATH="/home/deck/.steam/steam/steamapps/compatdata/XXXXXXXXX" %command% uplay://launch/2688/0 -eac_launcher
Played on Steam Deck OLED Game Mode. Graphics at Medium around 40-45fps
Installation process:
- Enter Desktop mode
- Use Lutris to download Ubisoft launcher then install the game.
- Add Ubisoft launcher to Steam, set proton version
- Start launcher from Steam, log in, then exit
- Find the compat data folder number
- Add launch options, replace XXXXXXXXX with compat data number
- Launch on desktop mode to "reinstall" the game (this should not download anything and just locate/verifying files)
- After game is fully working, exit game and return to Game mode

Work fine with default setting 43--48 fps high settings switch to med give almost 2h on battery life
Med Settings locked 40 fps

The Uplay launcher starts, is getting attchevements etc, shows that it's launching the game but then you get a black screen and the option (from steam) to press B to end the game. Thats all. Spash screen is not loading etc.
I've tried Proton Expirimental, 9.0 (Beta), 7 and 6. Also tried all startup parameters I could find.

-eac_launcher
Whenever an NPC is highlighted during hacking, the effect it uses is visually corrupted, not a game breaker just a minor problem I noticed when I switched to playing on the deck.
Sucks you have to sacrifice online to play on the deck, not a deal breaker, but a little sad. Though I don't think WD2 online even works on PC anymore? I've never gotten it to work.

In-game overlay causes performance problems. Can be disabled, but the setting is tricky to access (it is in the Ubisoft launcher settings)
Memory leak causes crash every 1-2 hours. The problem is fixed by disabling the in-game overlay and online settings.
Game runs well after disabling online settings and the in-game overlay. However not all the settings are available in the game or the overlay, and require accessing the Ubisoft launcher, which may be tricky.
A reliable way to access the Ubisoft settings is to run Uplay.exe with wine, e.g. via steamtinkerlaunch.
An easier but less reliable way is to launch the game without internet -- this will sometimes interrupt the startup process and send you to the Ubisoft launcher instead of the game, allowing you to adjust the necessary settings.
Text is very small on steam deck screen
The game crashes after a while due to a memory leak. Use the performance overlay to check out ram usage. Notice how it only goes up over time

uplay://launch/2688 -eac_launcher -nosplash
Adjusted graphics settings, core voltage(s), & tdp.
All text on your in-game phone is practically unreadable, regardless of video settings.
As mentioned, text is borderline unreadable, but only on your phone.
Unless this text issue is fixed I will not be able to continue playing.
Installed through ubisoft connect, ran fairly well out of the box at lowest settings. It worked very well through game mode!
Set the in game engine to 40fps, set the steam desk's screen to 40fps limit.
Forced Experimental, did not try to launch it any other way. Played while Proton next 7.0-6 was the newest release.
Bind some button to Shift+F2 to turn these stupid Ubisoft Connect notifications
Limit screen refresh rate to 45
You need to disable Ubisoft Connect notifications otherwise it will stay in up-right corner that you have outdated graphics drivers. The game will also crash randomly about every hour of gameplay. If Ubisoft would be so kind to shove it's launcher where it belongs, this would be a positive review.

STEAM_COMPAT_MOUNTS=/run/media/mmcblk0p1 %command% uplay://launch/2688/0
Installed Watch Dogs 2 through the Ubisoft Connect app then re-used the game entry for Ubisoft Connect inside of Steam to pass parameters which allowed the game to be launched through Ubisoft Connect. (I did not create a seperate game entry for Watch Dogs 2). At first performance was not good (0fps to 35fps) and it crashed when driving a car. To fix this, I lowered the settings to their lowest, capped the in-game monitor refresh rate to 60hz and set an in-game FPS Limit to 60 (setting these two settings stops the game engine from trying harder than it needs to). I also changed the Proton version to expiremental from V7.
After all this, the game ran at between 45fps and 55fps with no crashes when driving.
Uplay Shenanigans
Crashes randomly in Game Mode
EAC

%command% -eac_launcher -nosplash
Turned TDP so that the deck is capped at 40fps and set a 30fps limit in game
All text looks slightly blurry
Slight stuttering
Game would crash when driving around
Game runs very nice, highly suggest you play around with the settings as the game isn't well optimized.
Changed a couple of graphical settings and capped to 40 hz.

Enabled vsync in the game's video settings
Requires Ubisoft Connect login, Ubisoft overlay has popups that require a keyboard (shift-f2) to dismiss, but the Ubisoft overlay can be disabled in the Connect settings
I was required to launch the game from steam in desktop mode - it wouldn't get past the Connect window in game mode

Connect loads and I can sign in successfully, but the game window never loads. Tried proton 7.0 and experimental.