Team Ninja has made a considerable number of changes to the fighting game engine of Dead or Alive 4, but that's not all the development team has changed. There have been a good number of changes that will affect positioning and the environment (which has always played a major role in the DOA series). One of the biggest changes is in the tracking ability of attacks. While previous DOA titles allowed players to move around in a 3D environment, avoiding attacks was relatively difficult due to the fact that a vast majority of the attacks in DOA will track your opponent no matter how far around you they walk or sidestep.

This will no longer be the case with Dead or Alive 4, as sidestepping is now a very useful tactic. A properly timed sidestep will avoid just about any incoming attack, and leave your opponent open to a counter attack. Not only does this mean players on the offensive will have to be much more careful with how they attack, but players on the defensive will now have a reason to be continuously on the move. This will open up the game quite a bit more, and bring the environments even further into play as walls and obstacles will prevent sidestepping in a certain direction.

Speaking of walls, the wall stuns seem to have taken on a few changes as well. In DOA Ultimate, there were two types of wall stuns. You had the half wall stun where your opponent would hit the wall and fall down, allowing them to use a rising kick, or other means of attack to keep themselves safe. You also had the full wall stun, which stuck your opponent to the wall, forcing them to rise with their back to the wall (and without the ability to use a rising kick), or roll off the wall, leaving themselves open to attack.

Dead or Alive 4 takes a page from DOA3 by using a mixture of the two wall stuns and adding a wall bounce. From our observations, some wall hits will bounce your opponent off the wall, allowing you to follow up with a combo or juggle. Meanwhile, other wall hits caused the wall stick stun from DOA Ultimate, although it seems the ability to use a rising kick after a wall stick has been added. It also appears as though your opponent can counter after a DOA3 style wall bounce.

While many of the gameplay and environmental mechanics of Dead or Alive 4 have been taken from DOA3, a few have been taken from DOA Ultimate (DOA2). In DOA3, when you get knocked out of an area, the fall will kill you if your life is low enough. This is not the case in DOA Ultimate, leaving players with at least a sliver of life after a fall no matter how much health they had before the fall. DOA4 uses this same system to ensure players cannot die from a fall.

If you've taken a look at the DOA4 trailer from E3 or the Xbox Summit, you're probably aware of the ability to knock your opponent over a small barrier in the middle of the stage. In the Las Vegas themed stage, Hitomi knocks Christie over a small sign and Lei Fang knocks Bass over a small gating. In these instances, the players will be separated by the small median. In the past, the offensive player would automatically follow, which is still the case with larger knock offs. However, in smaller instances like this, players will have to manually jump over the median by tapping forward twice. Adding a punch or kick will perform an attack as you jump over. If you chose not to attack, you'll land in a while crouching status, meaning any crouching or while rising attacks can be executed instantly.

A few other minor changes have been made, such as the improved hit detection. Now attacks that look like they should jump over sweeps and other low moves will avoid them perfectly, while attacks that look like they should duck under high attacks will properly duck. In past titles this was not a reliable system, but in DOA4 things have been considerably improved.

All in all, one thing is very clear about Dead or Alive 4, the game is looking to move from a casual fighter with minimal depth, to a tournament caliber fighter. Currently Tekken, Virtua Fighter, and Soul Calibur are the only 3D fighters played in large tournaments, but with all of these new gameplay changes made to DOA4, it's looking to match those fighters in terms of depth. Of course, a few hours with the game is not enough to truly discover all of the changes Team Ninja has implemented, and with the game sitting at 60% there could be many more changes to come. But one thing is certain, anyone who overlooked the DOA series in the past due to its lack of depth will have to take a closer look when the Xbox 360 launches with Dead or Alive 4.