Halo is a gifted individual created as a result of the fusion of Gabrielle Daou, a deceased Quraci girl, with the spirit of a Motherbox. Imbued with mysterious aura powers, Halo is described as "an old soul in a young body" and doesn't view herself as Gabrielle anymore, choosing the new name Violet Harper, a name proposed to her by Brion Markov, in reference to her violet aura, and Will Harper. She and Brion were romantically involved until she witnessed Brion publicly execute his treasonous uncle.
After her resurrection, her original personality was wiped and she had no recollection of her past. As a result, she was extremely timid and meek, often acting afraid and uncertain of how to interact with her surroundings, sometimes exhibiting childlike behavior. Despite remembering English, she had great difficulty in communicating with others, usually resorting to one-word responses or gestures. Over time, she has improved her communication skills and grew more self-confident, largely due to her interactions with Nightwing's team and as she got a better handle of her powers and became able to manifest new abilities.
Much like Forager, Violet bonds with outsiders like herself rather quickly and seeks to help them the best way she can.
Violet is a slim, olive-skinned teenage girl with brown eyes and medium-length brown hair, though she wears a hijab to cover her head.
As Halo, she wears a form-fitting, black and gray unitard that covers her entire body, except for her face and fingers. It also has a hood with a violet stripe on its hem. Her arms are also adorned with colored stripes with an angular design: blue ones around her upper arms, red ones around her forearms and yellow ones around her hands. When she uses her powers, the stripes and the gray patch on her uniform, as well as her irises, turn to the color of her invoked aura, while her pupils and sclera swap colors.
Gabrielle Daou's dead body was thrown inside a grave by Henchy, Johann Mintz, and Piotor Platz, along with other failed Tar subjects. But as she was being covered up, a violet aura beamed from her and she sprang back to life. She tried to climb out of the grave, but Henchy and his men attempted to bury her alive. Fortunately, Tigress intervened and fought Johann and Piotor. When Henchy tried to use an energy whip against them, she unwittingly generated a red force-field, causing his whip to bounce back and knock Henchy out. She ran off with Artemis.
The revived corpse was largely discombobulated and had no memory of what had happened before the grave incident, including having no memory of her name. She could speak English, albeit with some difficulty.
Artemis instructed her to stay with Sphere while they rescued Superboy. As she watched Artemis and Jefferson Pierce walking towards the cliff, she uttered on word: "kill".
She followed them inside with Sphere, and when Plasmus was about to strike a deadly blow against Artemis, the girl shielded them with her red-aura power, firmly stating "no kill". Artemis was happy she didn't stay behind, despite her instructions, and dubbed her "Halo-Girl".
She made an escape with the Team, but Count Vertigo was able to track them down. In the ensuing skirmish, Halo-Girl manifested another aura—an orange one that allowed flight—when Plasmus grabbed her and burned half of her face off, though she didn't die and was able to heal herself back to normal with her violet aura.
After Plasmus—now released from Vertigo's control—was shot dead, Halo-Girl tried to heal him, but he was dead and could not be resurrected. That night, Artemis decided to take care of Halo-Girl and brought her to her place.
As Halo-Girl was sleeping two feet above their couch, Will Harper and Artemis discussed what to do with her.
Later, she walked with Artemis through a park and thanked her for letting her stay in. She spontaneously started levitating and Artemis told her to be more careful. Halo-Girl was remembering more English, but still couldn't remember her past life, except for the fact that wearing a hijab somehow "felt right".
Artemis told her that Dick was running a background check to find out who she was and return her back to her family. They proceeded to slip under a willow tree where they met Doctor Fate and Artemis asked if he could help with Halo-Girl's memories. Fate observed her and sensed an "old soul inside this young body", but Zatanna arrived before he could be asked to elaborate.
While Zatara and Zatanna conversed, Halo-Girl wondered what she and Artemis were doing there. Artemis explained they were not there for that part and asked her if Fate's words meant anything and if she had regained any memories. Halo-Girl remembered being buried, then being strapped to a gurney and hooked to an IV bag, then being abducted in Markovburg and finally hiding from Bialyan invaders. However, she simply told Artemis all she could remember was "darkness."
Later, when Artemis was comforting a grieving Zatanna after her father is repossessed by Nabu, Halo-Girl realized they were there for that part.
Halo arrived alongside Dick, Artemis, Jefferson via a Zeta-Tube hidden in Conner's garage. She spotted a computer screen with her picture and asked if that was her. Dick then started running a search in hopes of finding more about her background.
She went outside with Brion and told him he "seemed broken" and she felt the need to fix him. Brion started testing his powers, while Halo observed, impressed. The others arrived and encouraged Brion to test his powers. He ended up losing control and burned all his clothes away. Halo reassured Brion that he was nicely shaped and it was not his form that was broken. She told him to rest while the took her turn to test her powers.
Jefferson instructed her to switch between her auras to protect herself, while Artemis attacked her. Halo fended off and evaded her blows with her red and orange auras when suddenly she manifested a new yellow aura. She cautiously tested it and fired an energy blast that knocked her backward, crashing into a car. While Halo healed her injuries with her a violet aura, Brion said goodbye to her, calling her "Violet" and saying he couldn't stay. Halo asked him to stay, which he did after Dick promised to help him find his sister.
Halo was walking with Brion outside Conner's house when she suddenly got hungry, so Brion offered her an apple. Halo was delighted to try it, apparently for the first time in her life. Conner, Megan, and Artemis approached and introduce them to Forager. Halo was eager to share apples with him, and as soon as someone mentioned his home planet, New Genesis, Halo inexplicably started spouting information about it, without knowing where it all came from.
Halo, Brion, and Forager then stepped inside the Bio-Ship, which Megan had repurposed to be their new living quarters. When Brion announced his intentions to go after his sister on Infinity Island, Halo and Forager both offered to help, because according to Forager's reasoning, by sharing food between themselves, they belonged to the same "hive". Halo convinced Sphere to take them there, claiming they had a special relationship.
The trio arrived at their destination and as they made their way inside the island, Halo told Brion she wanted to have a civilian name, like Artemis did, and wanted it to be "Violet" because it was what Brion had called her the day before. However, Brion was too preoccupied with his quest to give her the approval and attention she was seeking. Suddenly, they encountered Sensei and Brion demanded him to reveal the whereabouts of Tara, but Sensei was not forthcoming and a fight ensued. Sensei snatched Halo and held her hostage. When Halo tried to use her powers, Sensei snapped her neck. Her body was thrown inside a prison cell, in front of a captured Brion, when suddenly she came back to life with her violet aura.
Halo, Brion, Forager, and Sphere were then extricated by Nightwing, Tigress, Superboy and Black Lighting. On their way back home, Halo declared that she wanted to stay with Brion and Forager, rather than joining the Team, thus forming a new team. Tigress then informed Halo that they had learned her real name: Gabrielle Daou, which jogged Halo's memories about her arrival in Markovia and the harsh treatment she received. This prompted her to put her past behind and assert herself a new identity: "Violet".
Halo was enjoying some time at the beach with Conner, Artemis, Brion and Forager, when Dick arrived with brand new uniforms for her and Brion.
Soon after, they started training and Halo displayed a better grasp in controlling and switching between her auras. At night, Halo had some s'mores, while the others congregated around a fire. When it was time for them to choose their code names, Halo had already settled on "Halo" and they resumed their training.
Later on, Dick, Conner, and Artemis congratulated the new recruits and treated them to complimentary s'mores. Halo was so happy that she manifested a new green aura, spawning holographic copies of herself around the others. This prompted Dick to start their training over.
The six tracked Cheshire down to a hanger and fought off her accomplices. Halo, Geo-Force, and Forager sparred with Shade, but he was able to redirect their attacks to each other with his shadow portals. Halo got knocked to the ground by a redirected Forager and Geo-Force charged towards Shade, who in turn opened a portal that swallowed Brion whole. Halo demanded Shade to return him, but he refused and teased her, saying he would keep Geo-Force forever gone. Enraged, Halo manifested a new blue aura that emanated a bright light, which overpowered Shade, forcing him to retreat and return Geo-Force. She ran over to hug him with relief.
As soon as Superboy arrived with Geo-Force and Forager in the Super-Cycle, Halo, who was already at the site with Tigress, greeted him with great enthusiasm. She was then greeted by Dr. Jace and apprised her of her new identify: Violet/Halo. Without warning, Nightwing unleashed a surprise attack on them. Halo instinctively dashed to shield Geo-Force and started to fight back once she and Forager realized it was a test. Nightwing eventually ceased the test and complimented Halo and Forager for their thinking and reacting fast.
While Nightwing and Geo-Force were having a row, Lobo crash landed and proceeded to attack Forager, claiming to have a contract to kill him. By Nightwing's command, Halo tried to extricate Forager out of the site, but Lobo skewered her with his hook gun and pulled her back. After healing herself, Halo generated holograms of Forager to confuse Lobo and shielded herself and Jace from his attacks. He then shot a couple of energy blasts, managing to sever Lobo's little finger. Lobo became enraged and tried to attack her and flung Black Lighting at them. Then she watched in horror as Lobo punched Forager to mush. Thankfully, it turned out it was just his exo-shell that he had shed to fool the assassin. Halo halted herself from hugging him though, because of his unappealing naked look.
Aura generation: Ever since her resurrection, Halo has shown the ability to generate multi-colored auras, each with a different power. All of her auras had manifested for the first time in moments of extreme distress or happiness. For a long time, she could only use one aura at once, being able to switch between them at will.
"Rainbow Power": After being repolarized by an X-Pit, Halo managed to unlock all of her auras, becoming able to use them all in concert. When she does so, she emanates an aura with the cascading colors of her different auras from red to violet, giving an appearance of a rainbow.
Multilingualism: Halo can speak English, Arabic and Old God.
In the comics, Halo was an original member of the Outsiders with photokinetic powers. Violet Harper was a runaway who lived a life of crime, until an altercation with Tobias Whale and Syonide killed her. Her essence was merged with an alien Aurakle, essentially resurrecting her. Plagued with memory loss, she started using the name "Gabrielle Doe". Her original body was later revived by Kobra as Spectra.
This is Halo's second animated appearance. She appeared, with no lines, in Batman: The Brave and the Bold.