Some might say it was a game that was simply too ambitious for its intended platform. In 2014, Ubisoft's spectacular Assassin's Creed Unity pushed back technological boundaries in a range of directions. Its depiction of Revolutionary Paris was dense in detail, packed with hundreds of residents on-screen at any given point, in a city that didn't just increase detail outdoors - but introduced highly detailed interiors too. Combined with big advances in character rendering and an astonishing global illumination system that still looks incredible today, Unity had all the makings of a masterpiece. The problem was, it didn't run very well at all.
Ubisoft itself admitted that the focus on technology was just too strong, to the detriment of the final product, which ran poorly on both PS4 and Xbox One. Even on PC, it took years for CPUs and GPUs to run this game well. Curiously, with the console builds, Unity actually ran better in some cases on the less powerful Microsoft machine, despite a locked 900p resolution on both - indicative of the extraordinary CPU load placed on the consoles and the small clock speed advantage enjoyed by Xbox One. Patches followed, the game improved, but it took the arrival of PS4 Pro and Xbox One X with their higher frequency CPUs to get the game running at anything close to a locked 30 frames per second.
Now, with the arrival of Xbox Series X, it's finally possible to play the game on console at 60 frames per second. And with one extremely minor exception, that's a locked 60fps. It's one of the most transformative experiences I've yet experienced via the new console's backwards compatibility feature - a game renowned for sub-optimal play is now basically flawless in performance terms. Actually breaking the 30fps limit of the game isn't easy though. It requires users to have access to the original disc release and to block any attempts to download any patches. This OG code is different from all the patches that followed by actually running with an unlocked frame-rate - a poor state of affairs back in the day for console users, but essential six years later in allowing us to leverage the huge CPU power offered by the Zen 2 processors within the next-gen machines.
With the arrival of Xbox One X back in 2017, we saw Microsoft's back-compat system solved many of the GPU-related issues in AC Unity, and simpler scenes could indeed hit 60fps. However, once we were out in the city streets, frame-rate collapsed. Even with a 30 per cent upclock vs the original consoles, the AMD Jaguar cores just couldn't get anywhere close to hitting the 60Hz refresh of the display. Series X does it, and does it in style, with a nigh-on flawless experience. Only when moving into the proximity of a co-op mission marker does the game momentarily lose its rock-solid performance level and even then only fleetingly. It's quite an achievement to see the Zen 2 cores deliver this - especially when you consider that it's the original, sub-optimal code that's playing out here, not the considerably improved patched update.
AC Unity on Series X not only looks better (and also benefits from forced 16x anisotropic filtering for cleaner ground textures) but it plays better too, and I reckon it's our last look at what you might consider to be classic Assassin's Creed: revisiting dense, thriving cities at pivotal moments in history. Many of its groundbreaking enhancements were stripped for the Syndicate follow-up, and it's fair to say that Asssassin's Creed as a franchise has moved in a very different direction since the arrival of 2017's AC Origins. Today, playing Unity at a locked 60fps says to me that if Ubisoft decides to revisit the classic formula and to enhance it, the CPU horsepower is finally there to bring back those huge cityscapes and to let us lose ourselves in their dense crowds.
Suffice to say, if you have a Series X console on preorder, be sure to find an old disc copy of the game - but remember not to install the patch when prompted. Hopefully Microsoft can make it all official by deploying its 'double fps' back-compat feature to this title because clearly the game code itself is capable of doing it, and it would open the door to the exact same experience also running on Xbox Series S. Yes, as AC Unity is CPU-limited on the existing machines, I see no reason at all that our experiment here wouldn't pay off just as handsomely on the junior next-gen console - but the irony is that its all-digital nature means that installing the disc code isn't possible. Perhaps a workaround might be found involving copying the OG code to an external device? Regardless, it would be good to get this working without the faff.
One final footnote. As we are running the original release code under back-compat, you may well encounter the various bugs that caused that strange mixture of amusement and frustration back in the day. Having sunk several hours into the OG release on Series X, my problems extended to nothing more than a phasing NPC and some glitching shadows in one room. Your mileage may vary of course, but I do recall original Eurogamer reviewer Tom Bramwell making his way through the game relatively unaffected by the issues. But still, from my perspective, Unity still holds up and annoying traversal issues aside (why does Arno clamber laboriously over the most incidental of bric-a-brac?) I've loved revisiting it. Enhancements from the Xbox compatibility team could go a long way - Series X could surely deliver 1800p60 - but maybe it's time Ubisoft stepped in to put things right officially. Next-gen opens the door to a beautiful Assassin's Creed Unity remaster, and I'd love to see that happen.
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