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Terminal.png This article, Theodore-A399, was written by Ahalosniper. Please do not edit this fiction without the writer's permission.
Biographical information

Theodore Serrano

Spartan Tag


Date of birth

March 12th, 2525

Date of death

November 7th, 2552



Hair color


Eye color


Affiliation and military information

ONI Beta-5 Division




Battle of Earth


Alpha Company (formerly)

"Bleeping glitches."
―Taser, in his usual speech.

SPARTAN-III Alpha Three-Nine-Nine, nicknamed Taser-A399, was a member of Alpha Company who washed out during training and remained on Onyx to serve as a drill instructor to both Beta and Gamma Companies. Born Theodore Serrano on Eridanus II to a pair of urban infrastructure managers, he grew up in close contact with the city's artificial intelligence program and learned a great deal about computers, often communicating in a peculiar computer-related speech. At five years old, Theodore's parents were killed by the Covenant during their attack on the planet, and he was taken to an orphanage on Falaknuma where he was recruited a year later for the first iteration of the SPARTAN-III Program.

During the course of his training, Candidate-A399 earned his nickname for his skill with computers and once nearly electrocuting one of their drill instructors with one of his own inventions. Sorted into Team Wasp with Valerie-A391 and A194, Taser looked forward to repaying the Covenant for the deaths of his family, but the opportunity was taken from him when the team strayed into a minefield near Zone 67. Taser attempted to disarm a mine which another trainee, A205, had activated, but made a mistake and was lucky to survive, though he lost both of his arms in the explosion. When flash-cloned limbs proved inviable for him, Taser was forced to accept robotic prosthetics, which at the time were not powerful or durable enough to serve a SPARTAN on active duty, and he was cut from the program as a washout, replaced on Team Wasp by the trainee whose life he'd saved. Though his first artificial arms were later replaced by THERMOPYLAE-grade prosthetics, Taser was left embittered by the loss of his chance to avenge his family, despite the opportunity he was given to stay on Onyx helping instruct future SPARTAN-IIIs.

Like the other washout instructors of Alpha Company, Taser made for a cruel and impatient mentor, and was twice confined to quarters over incidents. After the graduation of Beta Company, he befriended Aspen-B145, one of their medical specialists who'd washed out, and worked together training the members of Gamma Company. Thanks to Aspen's research into the augmentations of Project: CHRYSANTHEMUM, many of the former washouts were able to be augmented by the time of Gamma's graduation, and were brought aboard the UNSC Hopeful alongside them to be completely or partially augmented, and given an accelerated recovery schedule. Following their readjustment, Taser and Aspen were requested for a special project codenamed HIPPOCRATES being developed in the UNSC's development centers in Japan, and despite its non-combat nature, both of them accepted, working on a prototype medical variant of MJOLNIR Armor.

The project's success came in the nick of time, with the Covenant's assault on Earth coming just as they had a working prototype. While the first-phase Mark V MJOLNIR suit they'd modified went to Aspen, Taser received a set of his own Mark V[B] armor to work with, and took part in the defense of Tokyo during the planet-wide battle. Assisted by the Gammas of Team Machete, Taser and Aspen took part in the attack on Ryu Base by the Jiralhanae Chieftain Attilus, and came face-to-face with the Brute warlord to learn that he had been the one to personally kill two members of Team Wasp during Operation: PROMETHEUS. Succumbing to his long-starved hunger for revenge, Taser rashly engaged the Jiralhanae before Kodiak-G114 could arrive to help him and was swiftly killed by Attilus' gravity hammer. Kodiak managed to fight Attilus off, and recovered Taser's body and equipment, the data in his suit leading the Gamma's team to DAIMYO Base where they would discover a retired Deep Winter.

Personality and Traits

"A399 won't stall. I have an opportunity to balance the values. Executing."
―Taser's last communication.

Early in his training, Taser was an excitable recruit, eager about his training and the chance to fight against the Covenant. His intense study of computers led him to speak in a half-code digitalk that some of his fellow trainees found irritating, but nonetheless entered the SPARTAN-III vocabulary, such as "bleep" in place of curses. After his accident, however, the opportunity he'd lost felt like a false hope, and he was disgusted by most of the younger Spartans who would go on in his place. While some of the other instructors from Alpha and Beta shared the sentiment, it was the much calmer Aspen whom he would befriend, becoming his only friend as the rest were either dead or driven away by Taser himself. During the Battle of Earth, Taser was finally able to vent his aggression, but when he came face to face with the enemy who'd killed his old team, his anger got the better of him, costing him his life.