After many attempts, Warner Bros. has successfully patent the Nemesis System it introduced in Shadow of Mordor. Its various attempts over the years likely explain why many video games didn't adopt the Nemesis System into their own games, as while it was popular, it has been sorely missed in some key franchises that could benefit from it. Now, the patent is worded so ambiguously that anything close could cause some sort of dispute, and that could be bad news for the Assassin's Creed franchise.
Indeed, while not exactly a 1:1, the assassination structure of the Order of the Ancients in Origins and Valhalla, Cult of Kosmos and beyond in Odyssey, and presumably a similar system for the Children of Danu in Assassin's Creed Valhalla's Wrath of the Druids DLC all seem inspired by this system. That may not be exactly the case, taking out targets is a simple enough method, but the franchise seems stopped from ever taking this further.
Assassin's Creed Origins, Odyssey, and Valhalla Don't Have a Nemesis System...
The Nemesis System, in short, seemed revolutionary at the time. In-fighting led to randomized Orcs getting upgraded and becoming more powerful, while being defeated also meant that particular Orc was promoted. Every time one was killed, another would take its place. It ensured that, no matter how one played Shadow of Mordor, they always had enemies gunning for them. The menu system was rather simple, as player would watch the orcs move up, fight, and shift around, and it does seem similar to the menus found in Assassin's Creed.
Assassin's Creed Origins saw assassinations take a slight step away from the traditional structure, with Assassin's Creed Odyssey and Valhalla doubling down on this. Taking out the Cult of Kosmos and Order of the Ancients in the latter two titles required discovering clues, taking out lowering ranking members, and working their way up. There's no revolving door on members, as once the Order is defeated, it's done, but therein lies a big question for the future of the franchise.
But It Seemed like the Next Logical Step
Right now, the Assassin's Creed community is somewhat split over the direction of the franchise. Some love the RPG approach of the last few games, while others wished it would return to a more stealth-oriented game. As Assassin's Creed Odyssey went one direction with heavy RPG elements and AC Valhalla went another by bringing back old features and taking a "RPG-lite" approach, there is hope that somehow Ubisoft can reconcile the two ideas into one: an RPG with excellent stealth mechanics, one where the Assassin-Templar conflict is front and center and not side dressing.
The thing is, the Assassin-Templar conflict is never-ending. While eliminating these members in certain locations may cull one cell, there's always another and each faction is always recruiting. One way this could have been possible is to include a Nemesis System wherein players were constantly taking out Templars, having to sneak around as they cycled through new areas (heavy with stealth and parkour, of course), but one which put the Assassin-Templar conflict in the player's face and showed the futility of the fight, while still telling its own story. This, much like a return to a modern assassin character in the Assassin's Creed franchise, seems like a logical step.
After all, while it may not be a 1:1 for comparison, it's hard to look at the Order of the Ancients menu and wonder why no one has replaced The Ash-Spear, the Vellum, the Dart, and so on and so forth. Now, whether it was an idea cooking at Ubisoft or not, it's no longer possible for the game to demonstrate this conflict in such a manner. If it returns to the fore, it'll likely continue in the old ways as part of the main story; if it does not, then this system no longer has room to innovate, at least in this sense. Perhaps Ubisoft has another idea in mind for this franchise features, but for now, fans will have to wait and see what comes next.
Assassin's Creed Valhalla is available now for PC, PS4, PS5, Stadia, Xbox One, and Xbox Series X.