ATTN STEAMDECK USERS:

This game comes with UPLAY, which is required to start the game. However, UPLAY has been replaced with UBISOFT CONNECT. Does this mean it updates itself? NO. Support will tell you some guide that PC users have to do, but its a pain in the ass.

All UBISOFT has to do to fix this is replace Uplay with Ubisoft Connect within the install files on steam's servers, but Ubisoft Support are lazy asses and couldn't be bothered and just say "steamdeck is unsupported", even though it's still a hassle for PC users as well.

Long story short: Learn how to emulate the Switch and look into getting the Ezio Collection. save your money.
"The easiest way to stop piracy is not by putting antipiracy technology to work. It's by giving those people a service that's better than what they're receiving from the pirates." - Gabe Newell