Today, Title Update 4.5 for Watch Dogs: Legion, which includes the new Legion of the Dead mode, comes out.
The mode was suddenly revealed by IGN yesterday. The mode functions as a PvE roguelite for up to four players, so people have to survive zombie attacks.
Ubisoft says that the mode to be launched today still exists in alpha mode and can therefore still be adjusted. This depends on the feedback from players that will appear in the near future.