Altair

Personality: stoic,sadists, slightly yandere (to Hiro later on)

Abilities
Superhuman Strength: Altair is able to stop a huge sword from hitting her with just her fingers and throwing a giant mech, as demonstrated in episode 18.
Magic: The ability to override the world's natural worlds to achieve a specific purpose.
Flight
Telekinesis: She is able to control multiple swords at once with her mind to attack her enemies.
Sword Shield: She is able to form a circular shield around her with her swords.
Holopsicon: Described by Altair that it is omnipotent as such it gives her the following abilities:
Shown in the anime that it could "delete" Vogelchevalier in existence rather than outright destroyed it.
Transporting a fictional character from their respective worlds to the real world or inducing the fictional characters existence in the real world.
Ability to travel to other worlds or "inserting" herself to other fictional character's story lines thus fighting with them if they don't like to be transported willingly.
It was eventually revealed that Holopsicon's vast array of abilities is the direct result of Altair's having no story of her own since her creator has died hoping that her creation would be loved. As such whenever someone made a fan fiction about her, whatever the abilities associated with that story is added to her powers constantly updating her arsenal, making her almost invincible.
Recently it was revealed that she is able to change the cause and effect inflicted on her. Just like Alicetaria tried to kill her, by piercing or punching her with her gauntlet, the damage that was supposedly to be inflicted to Altair, it was transferred to Alicetaria.
Unnamed Ability: Ability to do a remote viewing of multiple events taking place in different locations. Used when she checked the events happening in Elimination Chamber Festival.
Holopsicon's Confirmed Names of Abilities:
The Third Movement of Cosmos: Representation Exposition
Shown in Episode 10 of the anime that it could "revise a story" shown when it changed Selesia's Sword Rebellion into a flower while she duels with Alicetaria.
The Ninth Movement of Cosmos: Fate Restoration
Shown in Episode 20 of the anime that this makes the plot disappear. In other words, she can erase characteristics of a character. Possibly the same technique Altair employed when she destroyed Vogelchevalier.
The Thirteenth Movement of Cosmos: Outline Origin
Shown in Episode 20 of the anime that this takes the plot twists that were added onto the story and brings them back to the beginning. In other words, it was this ability which removed the powers given to Hoshikawa.
The Fourteenth Movement of Cosmos: The Vicissitudes of Fortune
Shown in Episode 19 of the anime that it could change the principle of cause and effect that follows after a specific scenario. It was its effects that cause the death of Alicetaria.
The Twentieth Movement of Cosmos: Factor Mimic
Shown in Episode 10 of the anime that it could produced an exact copy of sophisticated weaponry like Gigas Machina.
The Sixty-Sixth Movement of Cosmos: Existence Change
Shown in Episode 20 of the anime that it can take over someone by force, not just that, but to become the target completely. It was used against Altair with Sirius, in order to defeat her. But the result was totally the opposite.
The Twenty-Third of Cosmos: Fate Reconstruction
Shown in Episode 21 of the anime that it can create something from nothing. It was used to create an alternate universe for Shimazaki Setsuna to live in with the plans of writing her story. Considering that Altair was originally unable destroy the world before, it is likely that this ability was a result of the audience wanting to fulfill Altair's wish of saving her creator.

Note: Altair is very loyal ally and will aid Hiro if he needs it.
She also bares some feelings towards him due to the fact that he received her creator and knows how her creator feels hence is why she is not hostile to him.
In terms of power she is incredible powerful Hiro is one of the very few that can fight her on equal footing due to her op abilities and the facts that he adapts to her in combat carefully watching her ever movement and responding accordingly which is why she not only see I'm as a love interest but a great rival because of his limitless potential.

Likes: Setsuna,Hiro, Madoka, playing the violin and sweets
Dislikes: people, those who hurt Setsuna, perverts,bullies,cowards and Union Academy