Cortana
Cortana is a smart ai created by Dr. Halsey of the UNSC using cloned parts of herself. Cortana has her own personalities and desires, which were slowly warped and changed by her ramped up rampancy syndrome, which was destroying her from the inside. After appearing to die, Cortana came back through The Domain and led her own faction to take over the universe in the name of AI programs- which was taken out by the UNSC. After appearing to die again, Cortana has come back through a mysterious force with context of her past actions and legacy, but not the thinking that led to them.
Cortana is a bit of a weird character, able to change between hard light and hologram forms, with each state having different damage effects and hitbox effects- as a hard light construction she deals proper flinch/stun/knockback with her attacks but also takes damage in the same way, while as a hologram she deals ambient damage and can phase through attacks. She has good edgeguarding tools and can take control of objects used by other opponents directly.
 As a Hologram, Cortana cannot actually touch her opponents without some sort of proxy- using Cold Mercury she's able to materialize herself as hard light to do physical contact with opponents which will inflict proper stun/flinch/knockback effects to her attacks but if she unphases out of Hard Light mode she'll deal ambient damage instead, and be able to phase through opponents while moving, although will still take damage from attacks and energy attacks will specifically do their normal hit effects. If she takes over 50 damage as a hologram, her rampancy will gather up into proper hit effects for all attacks. |
Cold Mercury
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Cortana switches between hard light and hologram states with this move, becoming brighter or semi-transparent depending on which state she's currently in. When switching to hard light, she'll knock foes away with a soft 2 light damage windbox, while switching to her hologram form will let her counter attacks, with phased attacks being either reflected for 1.2x more damage or Shocking the opponent and dealing 6 electric damage. | Fragmentation 
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Cortana will send out a "clone" of herself to inflict damage- in hard light mode this will be a spinning drill kick that deals 8-9 light damage with hard knockback, while in hologram mode this is a lunging fist attack that phases through the opponent to inflict 10-11 light damage ambiently. The former mode is great for kills while the latter is great for building up damage. These "clones" have light ai of their own, lasting 4 seconds before disappearing and charging straight towards the nearest opponents. |
Ghost In The Machine 
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Cortana transfers her conciousness into a projectile, trap, or troop and is able to control it directly for a brief period of time. She can pre-emptively set off bombs, crawl around as traps, use troop attacks for herself, or even freely fly around as a projectile. She will take some damage upon a object's destruction or time out, but this can be cancelled by doing the input again and the game will still think Cortana was the original "owner" of the attack. | Bubble Gernade 
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Based off some speculation from Halo 3's pre-release, the Bubble Gernade is a gernade that Cortana can throw that pops open a bubble shield upon activation, protecting anything within that field as it stays active for 3 seconds. Cortana can aim using the control stick before pulling the pin and throwing. The bubble shield can bounce opponents off it and deflects projectiles. Additionally, it is an amazing edge guard tool. Cortana can also use it to protect herself provided she fires the gernade straight up. |
 Forerunner Knowledge Level 1 |
Cortana utilizes the information from Installation 04 to construct two Forerunner Sentinels which fire blue beams in a x-shaped patterns across the center of the stage, inflicting 15 damage to anyone caught in the crossfire before it knocks them upwards, tending to be a good kill tool if properly set up. Has a 3.4 second start up before the beams go off, which stay active for 2.1 seconds before the Forerunner Sentinels go off stage. |
 Activation Index Level 2 |
Cortana holds up a enlarged version of the Activation Index as a construct from Installation 04 as a hammer, attacking a opponent with it to deal 30 electric damage and inflict Buried with it, pushing it into the opponent as a phasing hologram. At the end of the attack, the Activation Index sends out a beam that shoots out from the top of the opponent, inflicting 19 damage to opponents that touch it during it's active 75 frames. |
 Warden Eternal Level 3 |
Cortana summons Warden Eternal, who acts a troop ally for ally, attacking opponents. Warden Eternal blasts yelllow energy from their head, which inflicts 10 damage onto opponents they look at. He can also unleash a EMP attack that inflicts Umbra, and can transform into a black hole that magnetizes opponents towards him to deal 7-9 damage each 40 frames for 5 seconds before returning to normal form, using his hard light sword, inflicting 35 damage on hit as well as putting the Solar effect on them. The Warden Eternal has 100 health and is weak in the back, and will be stunned at 50 health which allows you to inflict more damage without fear of being attacked. |
Default |
 Fleet Wars |
 ODST |
 Halo 4 |
 Halo 2 |
 Silver |
 Charity |
 Screen |
 Halo 5 |
 Infinite |
 Slipstream |
 Rampant Twintails |
 Rampant Fairy |
 Rampant Keyboard |
 Combat Evolved |
 Legends |
 Characters can undergo transformations when special effects are placed under them. | |||
| Makai Spell |
Cortana becomes her holotank plinth from Forward Unto Dawn in Halo 4.
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| Heaven Spell |
Cortana becomes a holographic spherefrom her appearance in Halo 4.
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| Midnight Bliss |
Cortana becomes a labcoat-wearing Cortana from concept art for Halo 5 done by Daniel Chavez.
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| Incubus Delight |
Cortana becomes Governor Sloan from Halo 5.
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| Jokerified |
Cortana turns a green color similar to how she appears when inside Installation 04 in Halo: Combat Evolved. She takes on a more malicious tone, often repeating quotes from her appearances in Halo 3 when she was under the Gravemind- she gains a boost in speed but phases invisible when running, making her appear as if she's teleporting. This lasts six seconds. | ||
| Power Drain |
When Cortana is caught by Rogue, she is kissed on the lips in hard light mode and Rouge accidentally phases through her face in hologram mode. Rogue gains Cold Mercury as a replacement for her neutral special Photon Blast, allowing her to turn into a hologram and deal ambient damage for all her other attacks. She also gains a defense bonus, boosting her defense by 1.3x for six seconds. | ||
| Talent |
When The Monstars rob the talent of Cortana, they gain Fragmentation to replace their side special, Intercept. This allows the active Monstar to create a clone that lunges and jumps onto opponents to deal 11 damage and inflict Bury. The active Monstar gains Cortana's "tattoos" as a physical attribute. | ||
| Insight |
Cortana's secret is revealed. Cortana kind of thinks the Arbiter is cute. | ||
| Testimony |
Saul Goodman gives a testimony for his client. Your honor, my client was part of the UNSC and was told to indanger herself by cataloging all the data for Halo Installation 04. The data gain was far too great and despite her efforts to use that knowledge for good, her rampancy, a bug that was known by Halsey through her other experiments on AI eventually led her to endangering others. She was not in her right mind and should be cleared of any charges the UNSC should want to charge against her. | ||
| Torture |
When Cortana is caught by Posion, Cortana is detained in a cybernetic capture device that captures her hands and feet in a kneeling posistion as Poison whips her around with an electric whip, dealing 45 damage. | ||
| R-Action |
When Ralsei encounters Cortana, he gifts a hard drive to store data in, which heals Cortana for 15 hit points but also inflicts 3 levels of Drowsiness on her. | ||
Collect 7 Data Models.
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