An excellent addition to the Budokai family, though it may only appeal to DBZ fans.
One of the things I found annoying in Budokai 3, the Dragon Rush mode, has been removed. Also, there is only one life bar and one Ki bar, another thing that annoyed me in 3. Now there is a new bar called the Energy Gauge that fills during the course of battle automatically. Once the bar fills completely, one of three balls next to it turns blue, allowing you to max out your Ki gauge. Once maxed out, your character can do his special finishing move that does a whole lot of damage by pressing L2+Triangle+Down. These balls also allow your character to do Favorite Techinques By pressing L2+Circle(+Up). These techniques range from powerups to a Solar Flare that blinds your enemy.
The graphics, while not the best I've ever seen, are the best to date in a DBZ game. The character models are very well done and the Super Sayian golden hair is done perfectly. The battle arenas are also done very well with plenty of destructable objects, except for the rainbow colored barrier that keeps you from going out too far. This barrier gets annoying really quickly as you try to knock your opponent back and he hits the wall and gets right back up to attack you for a cheep shot.
The sound quality is not quite up to par with the graphics, but is still great none the less. There are times when the character voices will be drowned out and you can't hear them, or the character will say one thing and the subtitle will be completely different. But one of the cool things is that the Japanese voice actors are left intact for the game and you can listen to them instead of the English actors.
In terms of gameplay, the only real complaint I have is a figity camera whenever you get pinned next to the aformentioned rainbow barrier or a mountain. Other than that, gameplay moves suprisingly smooth, even in twoplayer. The splitscreen takes some getting used to, and I would have liked to see the option to be able to hook it up so that each player could have his own TV to fight in. The barrier kind of takes away from the feeling of freedom, but you quickly overlook it.
The main story mode, the Z battle gate, is the update to the Dragon Universe in Budokai 3. It allows you to play through the main battles in the series, as well as a butt-load of side missions from the movies and random fight created by Spike. A noticable missing saga is the Garlic Jr. saga. From here, you can earn skills (called Potora) to upgrade your character in in Z Evolution mode. You can also fuse these skills together to form greater skills and you can also fuse together characters from certain Potora. The unlockables in this game are amazing with over fifty charaters to unlock. There is also a Utimate battle mode where you rise through the ranks of 100 fighters, World Tournament, Practice, and Dueling modes.
This game is very tough, especially during the Z Battle Gate. You have one of three missions during a fight, beat up your opponent (easiest), finish off your oppenent using a certain attack (harder), and survive until the time runs out (hardest). Only by completing the restrictions can you advance in the Battle Gate.
Overall, this game is very well done and I don't think it deserves the 7 Gamspot gives it (no offense Gamespot >_