Naughty Dog has described The Last of Us Part II as one of the most ambitious games it has ever made. One of the major new additions is something that may not be immediately apparent, but will no doubt have a big impact on the game: a new traversal animation system.

Admittedly, "a new traversal animation system" may not sound exciting, but the implications of it certainly do. GameSpot attended a hands-on event for The Last of Us Part II and spoke to co-director Anthony Newman, who highlighted "motion matching" as one of the key new additions to the game.

"It's this technology for characters moving through a space like running, walking, jumping, and that kind of thing," Newman explained. "In all our previous games there's been this really distinct state machine where we say, 'Play a run animation. Then play a turn left animation. Then play a turn right animation.' The way motion matching works is it takes this massive bucket of animation, just hundreds and hundreds of animations, and chops them into little tiny bits. When you define the path that a player or an enemy wants to take, rather than saying, 'Play this and then play that and then play that,' the system actually looks at the bucket of animations, finds the ones that matches the path that you're already taking, and blends them together frame-by-frame."

The effect of this is, as Naughty Dog says, much smoother, more natural movement to characters. "It's this totally new way of doing traversal," Newman continued. "I think, as you play the game, you must have noticed just how fluid the player feels. With every foot plant, every turn, there's as little blending as possible. That's applied to our NPCs. That's applied to the horses. That's applied to the dogs. We even have these dogs and horses and mocap suits running around getting the data that we needed for this really intricate system."

A new gameplay video for The Last of Us Part II was shown during Sony's recent State of Play event. The video provides fleeting glimpses at some of the action scenes where this kind of movement will become most evident. More importantly, however, the trailer confirmed a release date for The Last of Us Part II.

We also learned that The Last of Us Part II will come on two discs, which is something of a rarity for PlayStation 4 titles. If you splash out for one of the special editions of the game, you'll get a note from co-director Neil Druckmann. You can read the heartfelt message from The Last of Us Part II's director in advance, however.

For more on the game, read our hands-on impressions for The Last of Us Part II.