After a year-long Uplay (Ubisoft Connect) exclusivity, Assassins Creed: Mirage has joined its predecessors on Steam. The game is priced at half its launch price and still requires the Ubisoft launcher. As expected, the concurrent player counts are fairly low, peaking at 7,870 players two days ago.
Source: N4G PC Assassin's Creed Mirage Optimized Settings: Best Graphics Settings for PC with Benchmarks