Indigo

Indigo is a Coluan known as Brainiac 8. She was considered the deadliest criminal on Fort Rozz.

Fort Rozz
Brainiac 8 was imprisoned on Fort Rozz when it was trapped in the Phantom Zone. After years of searching, she eventually finds the Kara Zor-El pod. She takes over the pod, causing the young Kryptonian to wake abruptly, and notices a computer console in her dashboard with a logo with three dots in a triangular shap before Fort Rozz's engines activated and both escaped the Phantom Zone.

Indigo
Taking on the alias "Indigo", Brainiac 8 travels through the internet with the hopes of wiping out all Humans on Earth. She tries to release private information about an infidelity website (DiamondDiscretions.com) to Catco, but Cat Grant refused to release it. The monitors and other electronic devices start to go haywire at CatCo and the hacker (who was Indigo taking on a human face on-screen) tells Cat that since she ignored what was on the drive, there is going to be chaos in National City. She keeps to her word and all the lights in National City turn green, causing major car crashes. At Kara's apartment, Kara and James Olsen watch Winn Schott try to crack the hacker's code to no avail when the hacker appears on the screen and teleports through the computer into the room as a blue woman with the symbols of Brainiacs. She attacks Kara, and threatens to kill Winna and Hank, but Hank and Alex arrive and scare Indigo off. Later, Indigo teleports through another computer and meets with Non, where it's revealed that the two had earlier sexual encounters. Indigo tells Non that Astra’s notion of living alongside the humans can’t work, and says she'll do something to the human race so she and the Kryptonians will be only ones left on Earth. At the military site, Indigo uses General Mathers' cell phone as a means to enter the base. She swiftly kills/takes out the officers in the room, and reveals a stretching power to turn both activation keys. Kara arrives and fights Indigo. Indigo eventually traps her with her legs, but Kara escapes and goes after the missile. Realizing that anything she tries could destroy National City, she finally relents to consult Hank, who guides and helps Kara disarm the missile's tracking computer. Indigo, initially infuriated her initial plan failed, tries to send more missiles, but is knocked down by Kara. Kara dropped her phone during the landing (not seen on screen) and Indigo uses the active device to reach Winn and choke him. Winn, though being strangled, continued to prepare his virus. Indigo begins to try to get Kara to back away, saying she (Indigo) is "invincible". Winn calls her a "glorified Windows Vista" and uploads the virus to Indigo. While she's being destroyed, she explains that if it weren't for her finding Kara's pod, none of them would have been on Earth at all. The virus finally consumes her, leaving no trace of her remnants.

Finally, Non, using the Omegahedron, shows that Indigo was not actually destroyed, with her body appearing on the computer board in severed pieces. Non says, "I merely broke your heart. Look what Supergirl did to you," and eventually says that he wants her to do things his way now.

Powers

 * Cybernetic interface: Brainiac 8 is a Coluan cybernetic being. She is able to transfer body in the form of digital code. She can interface with any machinery and manipulate computer systems.
 * Super strength: She has enhanced strength equal to a Kryptonian.
 * Invulnerability: Indigo's body is denser than a human's but not nearly as durable as a Kryptonian's.
 * Shapeshifting: She can take the from of a blue athletic female or a blonde human. She is able to manipulate her limbs to stretch to great length and create claws.
 * Self Repair: As a digital being, she is able to self repair.

Abilities

 * Expert hand-to-hand combatant: Indigo is an expert in unarmed combat.