Fanfic / Cast A Shadow

Cover art by Taliax

After losing to Aqua and Ventus and having his heart shattered along with the X-blade, Vanitas fell into the Realm of Darkness. Spending his time fighting off Heartless, he eventually stumbles across a familiar face currently fighting for her life.

Cast a Shadow is a story by Taliax with two sequels, Another Side, Another Shadow and Shadows Alight. It can be found on AO3 and on FFN.

Cast a Shadow and its sequels contain examples of:

• Adaptational Backstory Change: In the third story it's revealed that Ventus is originally from Twilight Town and that he got his keyblade from Lauriam.
• Adaptational Gender Identity: Aqua and Lea are both offhandedly mentioned as being trans. In canon, both characters are cisgender.
• Adaptational Heroism: Though he starts off as just as much of an asshole as his canon self, Vanitas gradually becomes more heroic and selfless thanks to Aqua's influence.
• And Then What?: When Vanitas first meet Aqua in the Realm of Darkness he considers just killing her, until he asks himself this.
• Chekhov's Skill: Aqua's color changing spell is used to trick Xemnas into thinking she’s been made into one of Xehanort's vessels.
• Clothing Damage: Aqua's constant fights with the Heartless began to damage her original outfit, so Vanitas offers to make her a Dark Suit to act as a replacement that can better defend against darkness.
• Dark and Troubled Past: Vanitas was trained by Xehanort so this is a given.
• Dark Is Not Evil: A big part of Aqua’s character arc is learning to accept that darkness is a part of her.
• Demonic Possession: Happens to Aqua twice. The first time she is possessed by a being referred to as the Dark Wind, who wants to use her body to escape the Realm of Darkness. The second Xemnas tries to turn her into one of Xehanort’s vessels, but she manages to fight him off.
• Drama-Preserving Handicap: When Aqua tries to get back into the Realm of Darkness to save Vanitas, she learns that they can’t simply create a Dark Corridor to get there, because it could allow the Dark Wind to escape.
• Dull Surprise: Aqua isn’t too surprised to see Vanitas in the Realm of Darkness. Word of God is this is because she accepted that any possible horrible thing that could happen to her will.
• Eldritch Abomination: Aqua and Vanitas accidentally awaken a being they refer to as The Dark Wind. It typically appears as a large mass of dark smoke and its true form is a horrific blob of hundreds of different Heartless.
• Emotional Powers: The Unversed are formed out of Vanitas' emotions, with different kinds of Unversed being tied to different emotions. He later learns how to channel his positive emotions to created light based variations he calls Inversed.
• Enemy Mine: Aqua and Vanitas very much hate each other, but have no choice but to work together if they want to escape the Realm of Darkness.
• Fire-Forged Friends: While initially barely tolerating each other, fighting off Heartless together and saving each other’s lives causes Aqua and Vanitas to become friends and later on, a couple.
• Giving Up on Logic: Aqua has this to say after she and Vanitas get ready to make ice cream
  Aqua: This is crazy. I’m going to make ice cream out of monsters made out of emotions, with the person who used to want to kill me, under a pit of quicksand in the Realm of Darkness.
  Vanitas: Yeah. So?
• Godzilla Threshold: When Lea and Riku are fighting Xemnas, Saix, and Xigbar, with Xemnas trying to make Aqua one of Xehanort's vessels, Lea decides to open a Dark Corridor and grab the attention of the Dark Wind. Unsurprisingly, it almost goes horribly wrong.
• Heroic BSoD: Aqua goes through this multiple times:
  • The first time she is on the verge of just giving up when Vanitas meets her in the Realm of Darkness.
  • The second time, she suffers a vicious panic attack after almost being possessed by the Dark Wind.
  • The third time is when she thinks Vanitas has died in the Realm of Darkness.
• Heroic Sacrifice: Vanitas gives up his chance to escape to Realm of Darkness in order to get Aqua out and prevent the Dark Wind from escaping with her.
• "Join Us" Drone: The Dark Wind literally says this once, and says other variants of the phrase on other occasions.
• Light Is Not Good: Aqua discovers light can be just as destructive as darkness when she uses large amounts of light to try and fight her own inner darkness, but only succeeds in causing damage to her own heart.
• Mook Maker: Vanitas can summon Unversed as usual.
• Mundane Utility: Vanitas uses one of his Unversed as an ice-cream maker.
• Needle in a Stack of Needles: Said almost word for word by Lea when he, Aqua and Riku search the Keyblade Graveyard for Aqua's original keyblade.
• Noodle Incident: When Lea and Kairi first appear, they're revealed to have crashed a gummi ship after Lea convinced Kairi to go on a joyride with him, while neglecting to tell her that he'd never flown a gummi ship before.
• The Only One Allowed to Defeat You: Vanitas saves Aqua from the Heartless because he wanted to be the one to finish her off.
• Power Dyes Your Hair: Literally. The very first spell Aqua taught herself was one to change the color of objects, which you used to change her hair blue.
• Power-Up Food: Aqua still has some of the stat boosting ice-cream she got from Disney Town.
• Power Incontinence: Vanitas' Unversed are drawn directly from his emotions and tend to spawn whenever he loses control of them, which has caused him some trouble post-Heel–Face Turn.
• Shout-Out: Parts of the lessons Aqua and Vanitas give each other about Light and Dark magic are taken from The Wheel of Time and its system of magic.
• Supernatural Gold Eyes: A typical side effect of using darkness is this.
• The Talk: Aqua has to give Vanitas one after he nearly groped her while trying to see if she had any food on her. He later gets another one from Isa while trying to understand the nature of his attraction to Aqua.
• That Came Out Wrong: After escaping the Realm of Darkness and confessing their love for each other Vanitas suggests that he and Aqua get out of their clothes, before clarifying that he meant buy replacement clothes for their dark suits.
• What Is This Feeling?: After spending time with Aqua, Vanitas starts feeling genuinely positive emotions for the first time in his existence and even begins creating light Unversed based on positive emotions. Aqua later experiences this as well, when the Realm of Darkness starts awakening her own inner darkness. This reaches a climax when Vanitas is forced to use a Dark Curaga to save her life, which fully awakens her darkness and amplifies her negative emotions.
• Wrecked Weapon: Riku's keyblade is broken in Shadows Alight during a fight with Xion.
• Yin-Yang Bomb: Aqua and her darkness combine their powers to expel Xehanort from their heart.
• You Are Better Than You Think You Are: After Aqua escapes the Realm of Darkness she’s worried that she isn’t worthy of being a keyblade master anymore after everything she’s been through. Yen Sid quickly convinces her otherwise.
  Aqua: But I’m broken!
  Yen Sid:(smiling) Aren’t we all?

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