"ZEXAL is a legendary power that once was able to save my world." — Astral to Yuma in episode 24.
ZEXAL (ゼアル Zearu) is a miraculous force from the Astral World in the Yu-Gi-Oh! ZEXAL anime. It is called upon by Yuma Tsukumo and Astral combining them into one being. While being used, the user is able to perform Shining Draw to create "ZW -" monsters that have the exact necessary effect to deal with situations the power was called for.
ZEXAL Morph (Xyz Change ZEXAL in the Japanese version, エクシーズ・チェンジ・ゼアル Ekushīzu Chenji Zearu) combines Yuma and Astral, with them referring to it as "overlaying" with one-another as in an Xyz Summon. During this time, Yuma and Astral are cloaked by aura: Yuma with red mist and Astral with blue mist, their souls combining into a new body. With this, Yuma/Astral wears a white spandex suit with red armor plating, his right eye becomes golden like Astral's left one, his hair turns gold and he gains a golden aura.
The power can only be used in a pseudo-space condition that is or that mimics alternate dimensions, such as inside the Emperor's Key or Sphere Field. Astral characterizes ZEXAL as a miraculous power that once saved the Astral World, while The Door describes as the ability that can "turn darkness into light".
While searching for Astral, Yuma's Deck case started to glow and he was brought to The Door. It tells Yuma about "ZEXAL", and Yuma is returned. While Astral was Dueling Kite and was fading, whispering Yuma's name, Yuma entered the computer chamber, and Astral shed a tear. The Emperor's Key reacted, and bursts with light, breaking the glass that surrounded it. The Key moved to Yuma, and sent him back to The Door. The Door opened, and Yuma telepathically talked to Astral, asking for his condition, and Astral tells him it is not going well. Yuma talked to him about ZEXAL, Yuma then runs through the door, of the edge of a dark cliff, and becomes cloaked in the red light that also appears during an Xyz Summon. Using its power, Yuma performed a Shining Draw, creating "ZW - Unicorn Spear" which negated the effects of Galaxy Eyes allowing Yuma to destroy it. This forces Kite to activate a face-down card that ends the Duel in a draw. He flees, allowing Yuma and Astral to retrieve the Emperor's Key.
The power was later used in Yuma's Duel against Trey in the gateway to the Barian World. After combining with Astral, Yuma drew "ZW - Phoenix Bow" and equipped it to "Utopia Ray" to destroy "Number 6: Chronomaly Atlandis", allowing Yuma to defeat Trey which prompted him to leave "Number 6: Chronomaly Atlandis" and "Number 33: Chronomaly Machu Mech" for them, as well as the final Heart Piece needed to compete in the World Duel Carnival semi-finals.
The power was again called upon during Yuma's Duel against Vetrix. After combining, Yuma drew "ZW - Lightning Blade" and equipped it to "Utopia Ray", preparing to retaliate against "Number 69: Heraldry Crest". He later acquired "ZW - Tornado Bringer" and combined it with "ZW - Lightning Blade" to create the first "ZW -" Xyz Monster "ZW - Leo Arms" to negate the effects of "Heraldry God" and destroy it, allowing Yuma and Astral to win the Duel and giving Yuma the title of Duel Champion.
During the final Duel against Vector and Dr. Faker, the power was utilized again. Yuma drew "ZW - Ultimate Shield" and activated its first effect to return "Utopia Ray", "Number C32: Shark Drake Veiss" and "Neo Galaxy-Eyes Photon Dragon" back to the field. He equipped "Ultimate Shield" to "Utopia Ray" and strengthened its DEF with "Xyz Unity" to transfer all 3 Xyz Monsters' DEF to the ATK of "Utopia Ray" and sending it to attack "Number 92: Heart-eartH Dragon". Triggering the other effect of "Ultimate Shield" negated the effect of "Heart-eartH Dragon" that would inflict effect damage, letting "Utopia Ray" destroy it and win the Duel. This released Dr. Faker from Vector's possession and temporarily ended the machination to destroy the Astral World.
Yuma and Astral used this power once again during their rematch against Alit, as a dedication to the Barian Emperor's honor and fighting spirit. Yuma drew "ZW - Eagle Claw" and equipped it to "Utopia Ray" giving it 2000 extra ATK and attacked "Number C105: Battlin' Boxer Comet Cestus", but was forced to activate "Eagle Claw's" second effect of negating and destroying a Trap Card in order to prevent Alit from inflicting effect damage on him using "Battle Rush". Alit then activated his face-down "Corkscrew Cross", allowing him to negate the effect of "Eagle Claw", and then inflict 500 damage to Yuma. Yuma retaliated by activating his Set "Last Chance", which could only be activated when Alit activated his Counter Trap Card; Yuma was able to choose one Trap Card from Alit's Graveyard and activate it as his own Counter Trap card. He selects Alit's "Counter's High", which was activated when Alit activated a Counter Trap Card during the battle. This allowed him to negate its activation and destroy it and all Battle Damage was doubled during this Battle Phase. "Utopia Ray" attacked and destroys "Caestus the Comet" winning Yuma the Duel.
ZEXAL allows Yuma and Astral to perform the Shining Draw (シャイニング・ドロー Shainingu Dorō) to create "ZW -" monsters that can be equipped to "Number C39: Utopia Ray". The cards are created with the effects needed to counter whatever the opponent has out. "Unicorn Spear" negated the effect of "Galaxy-Eyes Photon Dragon" during the Battle Phase, allowing "Utopia Ray" to fight it during Yuma and Astral's Duel with Kite. During Yuma's Duel with Trey, "Phoenix Bow" presented a way to deal damage to Trey which was nearly impossible due to the effects of "Chronomaly Atlandis". "Lightning Blade", "Tornado Bringer" and "Leo Arms" were created to help Yuma counter Vetrix's "Number 69: Heraldry Crest". "Eagle Claw" negated and destroyed the effects of "Battle Rush" to protect Yuma's Life Points from inflicting Alit's battle damage onto him.
The cards can be used outside of Duels, as Yuma used "Lightning Blade" to anchor himself and Vetrix to the walls of the Sphere Field in order to avoid being absorbed into the core. The Shining Draw can also be used with card effects that draw cards, with Yuma creating a "ZW -" monster and ""ZW -" support card in his Duel with Vetrix.
ZEXAL II also retains the ability to perform the Shining Draw.
Dark ZEXAL (ダーク・ゼアル Dāku Zearu) is an alternate form of ZEXAL. During Yuma and Astral's third rematch with Vector, the latter was able to manipulate the darkness inside Astral and stop the process. With Astral having lost faith in Yuma, the darkness within spread through Astral and he forcefully initiated ZEXAL again, sending the both of them into a black hole, which resulted in Dark ZEXAL. This form of ZEXAL has the ability to use the Dark Draw to create "DZW" monsters. Under its corrosive influence, Astral Duels aggressively; uncaring of the damage he takes. Meanwhile, Yuma enters Astral's mind, intending to save him. Yuma finds Astral's subconscious still in a state of corruption, believing that Yuma is no longer his friend. Yuma apologizes profusely, saying that he was at fault and is sorry for what he had done. He then runs towards Astral and embraces him, pushing both of them out of Astral's mind in the process. In the physical world, "Number C39: Utopia Ray V" attacks "Number 104: Masquerade Magician - Shining" one last time with "Utopia" at 83200 ATK. At the same time, Dark ZEXAL is reversed, with Yuma and Astral splitting apart as the others watch.
In this form, Yuma gains a darker appearance: dark brown skin, blue eyes, black hair, dark red armor and a purple aura surrounded by darkness. Unlike the normal ZEXAL, Astral has complete control over Yuma's body.
Dark ZEXAL allows Astral to perform a Dark Draw (ダーク・ドロー Dāku Dorō) creating a "DZW -" monster that can be equipped to "Number C39: Utopia Ray V". "Chimera Cloth" granted "Utopia Ray V" the ability to not be destroyed in battle and doubling its ATK and allowing it to attack again.
Yuma and Astral were eventually able to combine and form a stronger version of ZEXAL, ZEXAL II. In this form, they are able to use "Re-Contract Universe" to rewrite "Rank-Up-Magic Limited Barian's Force" into "Rank-Up-Magic Numeron Force" in order to defeat Vector. The energy was so powerful it even caused "D.D. Ancient Battlefield - Sargasso" to collapse. They still have access to Shining Draw. In this form, Yuma gains a black spandex suit with green designs resembling Astral's body markings and armor plating similar to "Number C39: Utopia Ray Victory". Yuma's hair grows longer to his waist and turns orange but keeps the red forelocks, and gains a golden aura and eyes. Unlike the other ZEXAL forms, Yuma no longer wears a Duel Gazer; instead, his left eye becomes more luminous, acting as the necessary mechanical component.
The upgraded ability appeared during the last turn of Yuma's third rematch against Vector. Yuma began his turn, drawing the last card in his Deck, "Rank-Up-Magic Limited Barian's Force", but he then collapsed. Astral said that his trust in Yuma is not what it was before, but adds that he still wanted to believe in hope and fight together. The two then perform a new ZEXAL Morph, called ZEXAL II signifying the revived bond between Yuma and Astral.The newly bonded duo activated "Rank-Up-Magic Limited Barian's Force" and performed a Re-Contract Universe, transforming their "Limited Barian's Force" into "Rank-Up-Magic Numeron Force". They activated the new card, Ranking-Up "Utopia" and Summoning "Number C39: Utopia Ray Victory" and negated the effects of all cards on the field other than "Utopia Ray Victory". They attacked "Umbralis" with "Victory", activating its effect to add the ATK of "Umbralis" to its own, winning them the Duel. The attack badly injured Vector, damaging his wing. Due to the power released during the Duel however, "Sargasso" began to collapse, ending Shark's and Kite's Duels with no result.
During their rematch against Dark Mist, Yuma and Astral utilized this evolved form once more and, using "Xyz Treasure", performed Shining Draw, drawing and subsequently used both "ZW - Sleipnir Mail" and "ZW - Asura Blow" to increase the ATK of "Number C39: Utopia Ray" ATK to 6000, while also allowing it to attack all of Number 96's monsters by the effect of "Asura Blow". Knowing the effect of "Number C96: Dark Storm", which dealt taken damage to both players, they used the effect of "Sleipner Mail" to make the ATK of Utopia Ray equal to that of "Dark Storm", which destroyed both monsters. Then, the effect of "Sleipnir Mail" activated, allowing ZEXAL II to Special Summon "Number 39: Utopia" from the Graveyard. "Utopia" attacked directly, winning them the Duel. In a final act of spite, Number 96 turned into an energy spear and surged towards ZEXAL II, forcing Astral to cancel the fusion and take the blow for Yuma, sacrificing himself to end the threat of Number 96 once and for all. 
While using ZEXAL II, Yuma and Astral are able to use a new ability called "Re-Contract Universe" (リ・コントラクト・ユニバース Ri Kontorakuto Yunibāsu), which allows them to modify the card they have drawn and bring out its true power. Against Vector, they transformed "Rank-Up-Magic Limited Barian's Force" into "Rank-Up-Magic Numeron Force", which alludes to the powers of the Numeron Code.
- ↑ 1.0 1.1 1.2 Yu-Gi-Oh! ZEXAL episode 24: "Hunting Down the Hunter, Part 2"
- ↑ 2.0 2.1 Yu-Gi-Oh! ZEXAL episode 66: "Sphere of Fear: Part II"
- ↑ Yu-Gi-Oh! ZEXAL episode 22: "The Shark Hunter"
- ↑ Yu-Gi-Oh! ZEXAL episode 49: "Crestfallen"
- ↑ 5.0 5.1 Yu-Gi-Oh! ZEXAL episode 67: "Sphere of Fear: Part 3"
- ↑ Yu-Gi-Oh! ZEXAL episode 71: "A Trio's Challenge: Part III"
- ↑ Yu-Gi-Oh! ZEXAL episode 86: "Counter Offensive: Part 2"
- ↑ 8.0 8.1 Yu-Gi-Oh! ZEXAL episode 111: "A World of Chaos: Part 2"
- ↑ Yu-Gi-Oh! ZEXAL episode 97: "Sinister Shadows"
- ↑ 10.0 10.1 10.2 10.3 Yu-Gi-Oh! ZEXAL episode 98: "Shadows End"