Game:Marluxia

Kingdom Hearts: Chain of Memories
Full Bloom: Marluxia will attack Sora with multiple strikes from his scythe. Petal Blade: Marluxia attacks from far away by creating shockwaves from his scythe. Flower Storm: Marluxia will create three petal whirlwinds that spread out around the area in a circular motion. If Sora is caught in one he will receive extensive damage. Then while Sora is trapped Marluxia will strike with his scythe.
 * Attacks

Blossom Shower: Marluxia rushes at Sora from above encased in an atom of blades three times before impacting on the ground and simultaneously launching a shockwave and unleashing energy petals that rain down on Sora. Deathscythe: Marluxia launches waves from his scythe to cause a shockwave to erupt from below Sora three times. Drop Shot: Marluxia drops from above, slamming his scythe onto the floor, causing a massive fissure.
 * Sleights

This fight is the first of the Marluxia final battles in Chain of Memories. Here, Marluxia's normal attacks consist of: Crescent Wave, an energy blade shot from his scythe, Phantom Cyber, a forward slash attack, and Circle Reject, a shockwave attack. These are the attacks that you have to watch out for. A good tactic for Phantom Cyber is to use a 0 attack card to break the attack and deal damage. The other attacks can be dodged by jumping over them. His two sleights, Deathscythe and Blossom Shower, on the other hand, are easy to dodge. For Deathscythe, all you have to do is head up or down towards the wall after he swings the scythe. If timed well, this can allow you to dodge the attack. Blossom Shower can also be dodged. If you use Dodge Roll at the right moment, you can nullify the damage the sleight would have otherwise caused. Dodging Marluxia's attacks as often as possible is the key to victory.

Kingdom Hearts: Re:Chain of Memories
In Re:Chain of Memories, Marluxia has a much different strategy from the GBA version; for example, Blossom Shower has changed completely from being just a Rose Petal Shower, to a long, virtually unavoidable sleight, and the Deathscythe sleight has gone from one strike to three, much faster strikes.

When the battle begins, Sora should be ready to Dodge Roll, or Card Break, because as soon as Marluxia plays an attack card, he takes no time in attacking. In Full Bloom, Marluxia will dash towards Sora and immediately start striking, so you should always keep a good distance from Marluxia in case he pulls this card. In Petal Blade, you have a little bit more time to react, but not much more, and Sora should either have a higher card ready or should just Dodge Roll towards Marluxia.

When Marluxia uses Flower Storm, it is always a good thing to be as far away as possible before he plays it, as with all attacks, that way you have time to run and find a card to break it.

The only positive way to survive Marluxia's Blossom Shower is to have the Auto-Life Vexen Card or have a 0 Card in place before the Sleight is played. In Deathscythe, if you don't break it, you should wait until you no longer hear his scythe spinning, and immediately Dodge Roll to the left or right of him, but you should not try to Dodge Roll endlessly. In Drop Shot, you should either try to Dodge Roll and keep yourself a moving target, Gliding takes too long to activate and the shockwave will hit you, but this sleight should give you enough time to pull a 0 Card.

You can also create a zero deck with at least 3 Cures.

Another strategy is to create a firaga deck, as strong as possible, and add a curaga and elixirs at the end. Keep spamming the firagas and you will see they deal a lot of damage, enough to kill him pretty quickly. This works with pretty much every boss except Axel, where you substitue homing blizzara for the firaga.

Kingdom Hearts II Final Mix
Marluxia appears as an Absent Silhouette and is also featured in the Cavern of Remembrance.

It is good to use the Guardian Soul in this battle as Reaction Boost is very useful here. As soon as the battle starts, Marluxia will whisper in Sora's ear, starting a countdown timer (the number above Sora's head represents his current level at the time). Whenever he hits you with his scythe, the countdown goes down by one. When it goes down to zero, Sora loses the battle.

Marluxia will use a number of attacks. He will conjure a black volley of vines around Sora, and will explode in a few seconds, dealing damage. To avoid this, Dodge Roll or glide around. Marluxia will also knock Sora into the air, and attack Sora over and over until parried (with Aerial Recovery/Retaliation). He will also use an attack where he spins his scythe into the air and attracts Sora into it, and attack, and the last one knocks Sora into the air. If this attack is guarded, you may use one of two reaction commands, the first being Rob Count, by standing near his scythe and hurling it at him (which restores the hit counter) and the second command, Air Trample, by standing near Marluxia, and damaging him. He also uses some regular attacks, and if the last one is guarded, he will be left vulnerable. He will conjure black circles on the floor, which will damage Sora greatly if Sora lands on them.

Marluxia will also turn into a wheel and head towards Sora. This can be blocked by guarding or Dodge Rolling. Marluxia uses a move where he begins to levitate over Sora, and summon pillars to deal damage. To avoid damage, glide or Dodge Roll around until he lifts up his scythe, and then use Reflect/Guard.

Marluxia is also one of the faster Organization members, and he warps around quite a lot.

Data Rematch
As aforementioned above, Marluxia is also available as a data replica boss. He, like other data bosses, has more health but his attacks and the strategy for defeating him remain the same. It should be noted that Marluxia's scythe attacks cannot harm Sora, but can reduce the counter. The only attacks in his arsenal that can hurt Sora are the black circles, the vine bomb, and the dark pillars of energy.

Trivia

 * The way Sora throws Marluxia's scythe at him through the reaction command, in the Absent Silhouette and Data battles, is identical to the way he does in the opening FMV in Kingdom Hearts II.