"Dissidia: Final Fantasy," with a cast drawn from Square Enix's long- running RPG series, answers the age-old question: Who would win in a fight between Tidus and Sephiroth? Or Cloud and Kefka?

Yes, "Dissidia" is a fighting game, but this isn't "Soul Calibur" or "Street Fighter" with a "Final Fantasy" skin. Mashing buttons and blindly attacking will accomplish little.

The roster includes an equal mix of heroes and villains, one of each from the first 10 "Final Fantasy" games, plus a couple of secret characters locked away at the start.

As in most fighting games, the goal of a match is to deplete an opponent's hit points and knock them out. Each character has a handful of moves, some in the air and some on the ground, and most of them don't do any damage – at least not directly.

There are two kinds of attacks: Bravery attacks and HP attacks. The latter chip away at a fighter's hit points and are key to winning a match. But the majority of attacks are employed in an ongoing tug of war over each fighter's Bravery score, which governs how much damage they'll do with an HP attack.

For example, if each combatant starts with 200 Bravery points, either one would do 200 HP worth of damage with an HP attack. If one character depleted the other's Bravery to 50, they'd have 350 points and do that much damage.

But Bravery isn't limited to the total of the two combatants' own scores. Each stage has a pool of bonus Bravery points awarded to whichever fighter can bring the other's Bravery to zero, called a Bravery Break.

Many matches can be won with only one or two HP attacks, and since a character's Bravery is depleted entirely if his or her HP attack connects, it's best to finish an opponent with one huge attack if possible, rather than several smaller ones.

Those are the basics of combat, but fighters have other moves at their disposal, which help make their battles fanciful and fast-paced. Characters can dodge or block incoming attacks, dash at each other from afar, even take their fight to the air. Each warrior has an EX Gauge that fills over time and can be given a boost with a special item on the field. When it's full, EX Mode can be activated to unleash a powerful special attack.

The game's graphics are excellent, and the action is speedy and generally easy to follow, though it's easy to get disoriented in the game's multilevel fighting arenas when not zeroed in on an opponent.

The main story mode offers a five-part adventure for each heroic character, capped by a battle with his or her rival from the original game.

In the story mode, characters go through several small grids littered with enemy "pieces," treasure chests and other items. Characters gain new equipment, abilities and greater power over time, and can be customized before going into battle.

PICKS AND PANS

Ninja Gaiden Sigma 2

3 1/2 stars

"Ninja Gaiden Sigma 2" brings last year's Xbox 360 action game to the PlayStation 3, but this is more than a simple port.

It reworks many aspects of the game; even for gamers who've played "Ninja Gaiden II," this update has surprises in store. Essentially unchanged is the action itself: Acrobatic master ninja Ryu Hayabusa is still deadly with a sword, a staff, claws or whatever other weapons he gets his hands on, and his ninja magic is powerful.

The violence has been toned down a ton in this version. Heads are lopped off in a haze of purple energy instead of blood, dismemberments are less graphic, and there's a lot less of the red stuff in general.

More substantial changes have been made as well. Levels have been redesigned and encounters remixed. There was no battle against a giant walking statue in the first stage of the original game, for example, and some of the cheaper aspects – fiery arrows flying in from offscreen, for instance – have been altered for the better.

On top of all that, there are three new characters to control, and a new cooperative Team Missions mode for off- or online play.

Sony PlayStation 3; $59.99 • Age rating: Mature

Ion Assault

3 stars

Instead of firing missiles or lasers or something like that, the player's ship in "Ion Assault" attracts particles floating in space, gathers them into a big glob and projects them at an asteroid or an enemy ship like a superheated snowball.

The amount of time the glob is charged determines its power, and various power-ups can augment the ion weapon or grant other effects. Targets don't take a set number of hits to destroy; instead, those particle shots heat up whatever they hit.

When a target is glowing, it's almost ready to pop, and firing at it again will destroy it, as will maneuvering close enough for a swirling mass of particles to edge it into oblivion.

The visuals are very nice, with the player's ship distorting space when its ion vacuum is activated, though the screen can get a bit busy at times.

There are several multiplayer modes: Two players can work together in the main campaign or compete in a versus mode that can also be played online.

Microsoft Xbox 360 (Xbox Live download); $10 (800 Microsoft points) • Age rating: 10-plus

– Justin Hoeger