3. Hack the game to not need to save games on a remote server.
This means a hacker has to figure out the saved game format, somehow jam into the application new code to write the saved data and new code to read it, TEST IT, and get it to work.
In most of the cases, there is no need to figure out the game format. Just read the binary data sent to the server and save it. Usually save game files are not that large and I suspect that most games read them at once to the memory.
Again you don't have to write a lot of code to do all these stuff. Just redirect whatever is sent to the Ubisoft server to a local server host in the same machine. This way the user can carry the save file anywhere. This is an added advantage for pirates while legitimate users should rely upon Ubisoft to save their game files for them. Heck, they can even play when the Ubisoft server is down, or even if there is no internet connection.
They could (probably have) limit that approach too by signing the data (as already suggested) or encrypting it with different keys for sending / receiving.
This means a hacker has to figure out the saved game format, somehow jam into the application new code to write the saved data and new code to read it, TEST IT, and get it to work.
In most of the cases, there is no need to figure out the game format. Just read the binary data sent to the server and save it. Usually save game files are not that large and I suspect that most games read them at once to the memory.
Again you don't have to write a lot of code to do all these stuff. Just redirect whatever is sent to the Ubisoft server to a local server host in the same machine. This way the user can carry the save file anywhere. This is an added advantage for pirates while legitimate users should rely upon Ubisoft to save their game files for them. Heck, they can even play when the Ubisoft server is down, or even if there is no internet connection.