Dissidia: Final Fantasy is an enjoyable game but it might be better suited for fans of the series.
Gameplay
Playing Dissidia: Final Fantasy is a lot like playing Kingdom Hearts. You move round freely on a battle map and can jump and attack, and pull off various techniques such as wall climbing or rail grinding, with a simple tap of the Triangle button. Using X to jump and Circle and Square to attack, you must string together combos to defeat your opponent. However, it isn't as simple as it sounds.
Whilst you and your opponent each have a HP bar, you also have an amount of "Bravery Points," which determine the power of your attack. The more Bravery you have the stronger you are and the more damage you deal to your opponent. Attacks executed with the circle button will not damage your opponent but instead steal their bravery and add it to yours.
As the battle goes on an amount of Bravery appears in between you and your foe's HP bars. Whoever can deplete their opponent's Bravery to 0 (which is called a Break) will gain all that extra bravery, which can give them hundreds, or thousands, of Bravery Points. When you think you have enough bravery you can use the Square button to use attacks which will damage your foe. Sometimes all you need to do is Break your opponent's Bravery and lock them into a Square-Button attack to end the battle.
You are allowed 12 attacks for use in battle; 3 for when your character is on the ground and 3 for when they are in the air, for both Square and Circle attacks. By moving the control stick in a certain direction you can unleash the other attacks you have assigned to a character, but since a majority of the time you spend will be locked on your opponent, doing so can be hard, and often quite frustrating; you might use the wrong attack, leaving yourself wide open.
When you win battles you gain rewards, including Gil (the game's currency), EXP, and even accessories. You can spend your Gil on weapons, armor and such to customize your characters with, and as your character levels up they gain new abilities and attacks, allowing you even more customization. And, the more you play, the more the game gives you, as you're constantly being showered with rewards. There is an immense feel of customization here, which is good for those who like to organize their characters.
Unfortunately, the game has a horrible camera; it can be controlled with the D-Pad but since you'll most likely be locked onto your adversary, it can be difficult to use. In large open stages such as The Rift or the Crystal World this isn't a huge problem, but in smaller cramped stages like Ultimecia's Castle or Kefka's Tower it becomes extremely troublesome; I remember all too well playing as Sephiroth in Ultimecia's Castle, as I stood on a platform in between a large, spiral staircase. As I locked onto my foe they started to rail grind on the spiral staircase, ascending it at a fast speed, making the camera spin around in circles, making me dizzy.
Graphics
The graphics of Dissidia are actually quite nice for a PSP game. It looks like an early PS2 game, almost like playing Kingdom Hearts (once again) and the special effects are very nicely done, particularly EX Burst attacks, which look fantastic. The special effects look quite nice too, and the game's opening cut scene is spectacular.
The cutscenes themselves throughout the story mode of the game are nicely done, but some cutscenes aren't as good as others, making them look a bit rushed, which is a shame. The voice acting is somewhat awkward in some parts too, which is another downside for a FF game.
Story
One of the biggest flaws of Dissidia is the story, as it just isn't told very well and it's not a particularly good story by my opinion. The God of Harmony Cosmos and the God of Discord Chaos are in the middle of a war, and they summon many warriors to fight, and there are only 10 left on each side; the heroes and villains of FF I through to X. You can play as these characters and even find secret ones, but only the characters on Cosmos' side are available to play as - the villains must be unlocked through the "PP Catalogue," where you spend points on rewards.
Dissidia: Final Fantasy is an immensely deep game that can offer more than your money's worth, even if it does have a few flaws; but it's a highly addictive game that is a must for fans, and one that non-fans should still consider looking into.