Marluxia

"Drown in the heart-lorn world of nothingness. I shall scatter your heart into the empty winds."

- Marluxia "As lightless oblivion devours you, drown in the ever-blooming darkness!"

- Marluxia "Imbeciles... You would knowingly shackle your heart with a chain of memories born of lies? You would be one who has a heart, yet cast aside your heart's freedom? You turn from the truth because your heart is weak -- You will never defeat me!"

- Marluxia before fighting Sora.

Marluxia, also known as the Graceful Assassin, is the eleventh member of the original Organization XIII and the main antagonist of Sora's story in Kingdom Hearts: Chain of Memories. He wields a scythe and the power of flowers, which represent death as opposed to how they represent Cure magic in the games for all the other characters. Marluxia, along with Larxene, another Organization XIII member, schemes to overthrow Xemnas, with the help of Sora, so they can become the leaders.

Kingdom Hearts Union χ
Lauriam, Marluxia's original self, was a Keyblade wielder seemingly chosen by Master Ava to lead the Dandelions during the First Keyblade War. He was one of the five leaders, alongside Ventus, Brain, Ephemer, and Skuld. He appeared shortly after an unknown person murdered Strelitzia, a Keyblade Wielder also chosen by Master Ava to lead the Dandelions, stole her book, and took her place amongst the leaders.

Before Kingdom Hearts 358/2 Days
At an unknown point in time, Lauriam succumbed to darkness, turning his heart into a Heartless. However, his will was so strong it left behind a Nobody, who was recruited into the Organization by Xigbar and Xaldin.

358/2 Days
Marluxia appears as a playable character in Kingdom Hearts 358/2 Days, and teaches Roxas a few things about fighting.

Chain of Memories
After the events of the first game, Sora, Donald, and Goofy are wandering a long road. In the middle of the night, a hooded Marluxia appears and leads them to Castle Oblivion. Once inside, he takes all of their memories, and puts them into cards, weakening the party. He then teaches them how to use the cards, and then leaves after giving them a card that allows then to revisit a world from their memories.

As the game goes on, it is discovered that Marluxia has gotten fellow members of the Organization Axel and Larxene to help him conspire against the leader of the Organization, Xemnas. To do this, he wishes to use Naminé to twist Sora's memories, turning him into a slave of the Organization, so that the power of the Keyblade could be theirs. However, Vexen is killed by Axel after his defeat against Sora to prevent him of revealing theirs plans, Larxene is killed by Sora, Goofy and Donald, and Axel betrays him, leaving him the last person in the conspiracy.

Sora makes it up to the floor with Naminé, and after a short talk Marluxia reveals himself, and demands that Naminé use her powers to crush Sora's heart, but Naminé refuses, and Marluxia fights Sora. Sora is able to overpower him, and he flees into the highest room in the Castle, awaiting Sora with a reaper machine to help him fight. After that he fights Sora with an angel-like nobody, which is the ultimate proof of his powers. In the end, Marluxia still falls at Sora's hands.

Kingdom Hearts II Final Mix
Marluxia's spirit remains as a special kind of Nobody, called an Absent Silhouette, and manifests itself inside the Beast's Castle in the Beast's room after Sora convinces the Beast to take back Belle and the rose from Xaldin. If Sora chooses to investigate the Silhouette, Marluxia reappears and engages Sora in a hectic rematch, but is defeated. A data replica of Marluxia also appears in the Cavern of Remembrance.

Kingdom Hearts III
Marluxia is stated to reappear in Kingdom Hearts III as part of the real Organization, despite his attempts of overthrowing the original. He encounters Sora, Donald and Goofy at the Kingdom of Corona and notes how it is interesting to see Sora again. The latter did not recognize him, since their memories of Castle Oblivion have been wiped clean.

Quotes
"Well, there you have it. Welcome to the fold, Roxas. We'll set out once you're ready."

- Marluxia talking to Roxas for his paired mission with him.

"Roxas, was it? I never properly introduced myself. I am Marluxia, Number XI."

- Marluxia introducing himself to Roxas.

"Lucky Number XIII... At last, a chosen wielder of the Keyblade amongst our ranks."

- Marluxia talking about Roxas.

"Hmph. Nothing to be feared. So, Roxas, shall we put that power of yours to a little test? Use your Keyblade... and defeat those Heartless."

- Marluxia telling Roxas to defeat some Heartless.

"Dark creatures who roam about, searching for hearts. They come in two larger varieties. The ones you just defeated are known as Purebloods. Purebloods don't release any hearts when you defeat them. In other words, don't bother with them. Your mission is to collect hearts, after all. The other variety--"

- Marluxia explaining the Heartless to Roxas.

"None. So long as the Heartless are felled by your weapon, the Keyblade, the hearts will be captured."

- Marluxia talking about the Keyblade and hearts.

"They will gather as one, and create an almighty force known as Kingdom Hearts."

- Marluxia talking about Kingdom Hearts to Roxas.

"The rest of us can defeat Heartless, but we have no way of collecting the hearts they release. Eventually, the hearts will turn right back into Heartless. You see, then, how special you are?"

- Marluxia talking about how "special" Roxas is.

"That Keyblade... The things that could be done with that sort of power..."

- Marluxia after looking at Roxas's Keyblade.

"Shall we RTC, then?"

- Marluxia after completing the mission.

"The Keyblade wielder's power... How fascinating."

- Marluxia talking to Roxas at Day 10.

"If only we'd met sooner, Roxas... You would have made a fine addition."

- Marluxia talking to Roxas at Day 15.

"In this place, to find is to lose and to lose is to find. That is the way in Castle Oblivion.""

- Marluxia upon the start of Sora's Story.

"Here you will meet people you have known in the past, and you will meet people you miss."

- Maluxia.

"If what you want is to find him..."

- Marluxia about Riku.

"I merely sampled your memories, and from them... I made this. To reunite with those you hold dear..."

- Marluxia before giving Sora his first cards.

"Vexen, the simple fact is that your project was a failure. You'd best not disappoint us again."

- Marluxia talking to Vexen.

"I've been entrusted this castle and Naminé by our leader. Defying me will be seen as treason against the Organization."

- Marluxia threatening Vexen by reminding him of the position Xemnas granted him.

"You have some nerve to show your treasonous face around here. Some nerve indeed."

- Marluxia talking to Axel.

"Why let Naminé go? If it weren't for your needless meddling, we could have turned the Keyblade master to come and serve us."

- Marluxia talking to Axel about Naminé.

"Since when were you suspicious of us?"

- Marluxia talking to Axel.

"So you only eliminated Vexen to obtain proof of our plan?"

- Marluxia discovering why Axel wanted to join his conspiracy.

"Are you listening, Sora? Axel says he's willing to harm Naminé to get me. You won't let that happen, will you?"

- Marluxia manipulating Sora to fight Axel.

"You've defeated Axel. The Keyblade's power-- how I've longed to make it my own."

- Marluxia upon entering the final room in Castle Oblivion.

"You've no chance of winning. Naminé... Erase Sora's memory."

- Marluxia ordering Naminé to erase Sora's memories.

"I'd rather prefer him unmarred, but he can be rebuilt-- to my liking with time. Naminé, do it."

- Marluxia talking about Sora and forcing Naminé to wipe Sora's memories.

"Your heart will be scattered!"

- Marluxia when activating his Limit Break.

"Sink into the darkness!"

- Marluxia when activating his Final Limit.

"Hmph! So you are a hero!"

- Marluxia when defeated.

"Your hopes are doomed to the darkness!"

- Marluxia upon being defeated.

"So this... This is the heart of a hero!"

- Marluxia when defeated.

Trivia

 * Marluxia was originally planned to be female, but the idea was scrapped to avoid the implications of two women trying to overthrow a male-dominated Organization.
 * In supplemental material such the KH Ultimania guides, it is stated that Marluxia is the third most powerful member in Organization XIII (surpassed only by Roxas at his full power and Xemnas).
 * All musical pieces used during the battles against Marluxia in Kingdom Hearts: Chain of Memories and Re:Chain of Memories are named after his overall concept:
 * The first piece "Graceful Assassin" is also his title.
 * The second piece "Scythe of Petals" alludes to his weapon.
 * Finally the third piece, "Lord of the Castle," refers to his status in Castle Oblivion.
 * In the English version, Marluxia is voiced by Keith Ferguson, who also voices Bloo from Foster's Home for imaginary Friends and Gabriel Reyes/Reaper in Overwatch. In the Japanese version, he is voiced by Tatsuya Kando in the original version of Chain of Memories, and by Shuichi Ikeda in Re:Chain of Memories, 358/2 Days, and II Final Mix.
 * The location of Marluxia's Absent Silhouette is eerily fitting for him, as the Beast's Room also contains his rose. The rose's curse represents how long it takes for the Beast to slowly lose his humanity, and by the time all of the rose's petals fall, the Beast's humanity will be effectively dead. Considering Marluxia's attribute being flowers, the location is almost appropriate.
 * Before Re:Chain of Memories (which had extensive voice acting), many English-speaking fans assumed Marluxia's name was pronounced "mar- lux-ia" rather than "mar loo sha".