There's a new Assassin's Creed game every year, but Ubisoft still manages to wow us with some new feature or another when they inevitably roll out a new title at E3 each year. At the latest expo we were treated to Assassin's Creed Unity's four-player co-op missions. But that isn't the only new addition to the game.

In a demo during E3 2014 the game's Technical Director James Therien showed off new features ranging from a totally redesigned parkour system to the numerous ways semi-scripted events can unfold in the game's hyper-detailed version of French Revolution-era Paris.

"We redid the navigation from scratch," Therien said as he demonstrated Unity's new downward parkour mechanics. To descend from high places you can hold the right trigger and press the "B" button instead of needing to drop down into a soft haystack or slowly scale down inch-by-inch. Your Assassin finds a path down the building, leaping and swinging as he does when he's climbing up.

There's also a stealth button—finally! Assassin's Creed III introduced "stalking grounds" like high grass where the Assassin Connor would automatically go into stealth mode. But now players can make that choice anywhere, reducing the noise they make while moving in and out of cover as they watch enemies' movements and prepare to strike. 

In spite of Assassin's Creed IV: Black Flag's current-gen versions on Xbox One and PS4, Unity is the first game in the series that truly looks like it belongs on these powerful consoles.

Combat has also been revamped, Therien said. In past Assassin's Creed games it was usually simple to defeat even large numbers of opponents, since only one or two would ever attack you at a time. Now if you're facing more than a few enemies your best bet is to run away and hide. "They're going to shoot at you," Therien said. "Basically you have to either get away or rethink your situation and come back in."

The mission we saw involved following a French captain through Parisian crowds and eventually killing him while peasants fought with soldiers and people cried or screamed in the streets. It was the same demo seen during Ubisoft's E3 press conference, only now with the benefit of Therien being there next to us to narrate his gameplay and answer our questions.

The game is set during a tumultuous time for Paris, but that only slightly detracts from the city's beauty. Luckily the game's indoor environments are connected seamlessly to the larger city, and you can go in and out of buildings as you please without any loading screens. In spite of Assassin's Creed IV: Black Flag's current-gen versions on Xbox One and PS4, Unity is the first game in the series that truly looks like it belongs on these powerful consoles. Clothing moves realistically, faces have incredible detail—it's simply gorgeous to behold.

"It's a very multi-layered city," Therien said. "We spent a lot of time trying to capture the essence of the light and of the air." They want you to spend more time in that air rather than looking at menus and mini-maps, so a new "high-ground icon" feature lets you view map icons—such as assassination contracts and merchants that are located nearby—as a handy overlay. 

As he traversed the streets of Paris, our Assassin flitted in and out of buildings, even picking up side missions as he went. And in Unity you can have multiple missions active at the same time. Emergent events like the random courier appearances of previous titles—including fights and chase missions—happen with much more variety and frequency now, Therien said.

As he approached the location that would become his target's final destination, the captain ordered a man's head to be guillotined off. It seemed like a preventable event. However, Therien said no matter how fast he'd traveled to the end of the mission, he's never been able to save the poor bastard. So while the world is malleable to some extent, it remains to be seen just how much you can affect Unity's scripted events.

Regardless, the promise of co-op missions should be enough to get fans interested in the latest Assassin's Creed game. The main story will still be entirely comprised of single-player missions, but there are hours of other specially-tailored missions that let you play with friends or get matched with strangers. You can also enter other players' games without any missions active, just to mess around or say hi.

After all, sometimes even Assassins need a friend.

Assassin's Creed Unity comes out October 28, 2014 for Xbox One, PlayStation 4 and PC.

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