Omega

Omega, born as Peylix, also called Omegon and worshipped as Ohm, was a great intergalactic engineer and co-founder of Time Lord society, but centuries of loneliness and isolation bent his mind so that he threatened the entire universe. He was the only person ever to live within the anti-matter universe, which he subsequently ruled over while he used his will to enable him to construct a landscape, with the permission of the anti-matter creature. However, his existence in this realm robbed him of his body and left only his conscious will intact, a realisation that twisted him into murderous insanity aimed towards the Time Lords, whom he blamed for abandoning him to his fate.

Omega was one of the most significant figures in Gallifreyan history. He appeared in the ROO texts, as later scholars on Gallifrey would call them, alongside Rassilon and the Other. (PROSE: Goth Opera, The Infinity Doctors)

Becoming Omega
Omega, whose original name was "Peylix," (AUDIO: Omega) and Rassilon were born in an era of Gallifrey's history when the Gallifreyan civilisation was turned outwards, perfecting more advanced forms of interstellar travel to guide the development of less advanced cultures and set themselves up as Gods. Rassilon and Omega were among the only Gallifreyans who gave much thought to the future and destiny of Gallifrey. (PROSE: The Legacy of Gallifrey)

Rassilon and Omega became friends, with Rassilion even allowing Omega to call him "Rass", yet Rassilon was also very dismissive towards his friend. Peylix was left with the nickname "Omega" after he had received the "Omega Grade", the lowest mark possible, for an essay he had written that explored the possibilities of increasing the Gallifreyan power by exploding a star, and harnessing the resulting energy for time travel. His teacher, Luvis, saw the plan as "madness and pure idiocy" and made Omega the first person to ever recieve the grade. Rassilon argued the new nickname gave Omega a reputation and made him known to the public. (AUDIO: Omega)

Rassilon and Omega became solar engineers, a respected class of scientists among the Gallifreyans. While Rassilon dreamed of immortality, Omega, believing immortality to be impossible, turned him over to the prospect of developing time travel. (PROSE: The Legacy of Gallifrey) In spite of the Omega grade he recieved on his paper about the subject, (AUDIO: Omega) Omega and Rassilon worked on the project for several years until they had developed the final form of the plan to detonate a black hole and funnel its power back to Gallifrey, which they presented before the Gallifreyan Council. They were initially dismissive, but Tussan's cat spoke out in favour of the two engineers and they received the funding their needed. (PROSE: The Legacy of Gallifrey)

According to one of Omega's unreliable memories, at a time when Omega still wanted to be known by his birth name "Peylix," Omega and Rassilon were only able to begin their experiments after a revolution occurred on Gallifrey. Although Omega pleaded for Rassilon to stop it, his friend argued that it was the only way to remove those who opposed their progress. Afterward, Rassilon became a politican, while Omega carried on as a scientist. (AUDIO: Omega) According to another account, Omega and Rassilon were both already members of the High Council when they carried out their time travel experiments. (PROSE: A Brief History of Time Lords) The Eleventh Doctor later recounted that Rassilon had been "Omega's boss." (COMIC: The Lost Dimension)

By the time of the experiment and his "death", Omega had married a Gallifreyan known as Patience. (PROSE: The Infinity Doctors)

Achievements
Alongside Rassilon, Omega played a part in the creation of the living metal Validium. (TV: Silver Nemesis; PROSE: A Brief History of Time Lords) Omega was more popular than Rassilon amongst the Gallifreyans; Rassilon was a politican and heavily disliked, whereas Omega had become a public hero. (PROSE: The Legacy of Gallifrey, AUDIO: Omega)

With the help of the Other, (PROSE: Lungbarrow) Omega and Rassilon enabled the people of Gallifrey to achieve time travel by using the Hand of Omega, a stellar manipulator which could make stars go supernova. (TV: The Three Doctors, Remembrance of the Daleks) In an abnormal state of history, it was said that two Hands of Omega existed. (PROSE: The Infinity Doctors)

Omegon told K9 Mark I that he had "harnessed the power of a thousand suns" to create the system that gave the Time Lords the ability to travel in time. (PROSE: K9 and the Time Trap) According to other sources, it was with the power unleashed by a single supernova (TV: The Three Doctors) or, in subtly different accounts, the detonation of an existing black hole, (PROSE: The Legacy of Gallifrey) that Omega hoped to generate enough power to travel through time. (TV: The Three Doctors) As Gallifrey's galaxy had only one Population III star at that time, they decided to destroy that one. (PROSE: The Infinity Doctors) The star, in an area known as the Sector of Forgotten Souls (AUDIO: Omega) in the constellation of Ao, (PROSE: Lungbarrow) bore the name Qqaba. (COMIC: Star Death, PROSE: The Infinity Doctors)

According to a transmission from Anathema, which may have been influenced by Faction Paradox propaganda, when Rassilon first attempted to create and harness the power of a Black hole, before Omega's development of the stellar manipulator, he accidentally punched a hole into another plane of existence, and the Great Vampires swarmed into the Gallifreyans' universe, beginning the Eternal War. According to this source, an engineer strongly hinted to be Omega subsequently plugged up the black hole, making it resemble an ordinary planet. (PROSE: Interference: Shock Tactics)

The "death" of Omega
The Fifth Doctor once reflected Omega had "always been a victim of circumstance". (AUDIO: Omega) According to most accounts, Omega was lost during the very same great working by which he granted Gallifrey the power to travel in time: the stasis halo of Omega's Starbreaker, the Eurydice, was sabotaged, exposing it, and the Starbreaker's crew, to the fury of the black hole. There were several accounts concerning the details and reasons for the sabotage, (COMIC: Star Death, AUDIO: Omega) though one Gallifreyan wrote that Omega had "got his sums wrong" and was simply not within a safe distance when the star exploded. (PROSE: A Brief History of Time Lords)

Historically accounts depicted that Omega's assistant, Vandekirian, had sabotaged the mission on behalf of Rassilon. However, feeling guilty over his betrayal, he cut off his own hand as recompense. Omega did not accept it, and cut off his other hand, placing it in his stellar manipulator, which was later to be known as the Hand of Omega. Upon which, the Eurydice was destroyed due to Vandekirian's actions. The hand was only named after Omega because Rassilon wanted to use the public's love of Omega to boost his own popularity, reasoning that showering the fallen founder with praise would do better than doing so for the disliked Vandekirian. (AUDIO: Omega) According to the Seventh Doctor however, the Hand of Omega was not "literally" a hand, but had instead only received this nickname figuratively, "because Time Lords have an infinite capacity for pretension". (TV: Remembrance of the Daleks)

In his own distorted memories after taking on some of the Fifth Doctor's biodata, Omega recalled that Vandekirian was at least partly responsible for the sabotage. He had discovered that detonating the star would jeopardise the existence of a race called the Scintillans. When he realised what would happen, Vandekirian's guilt caused him to destroy his own hand, since its activation required his palm print. However, Omega cut off the man's other hand to activate it anyway, no matter the consquences for the Scintillans, before killing Vandekirian himself. When Omega began to have these memories involving the Scintillans, he was filled with guilt, despite having tried to argue that the reward of time travel for Gallifrey had justified his means.

However, the Doctor revealed that the history with the Scintillans was a corruption of his own memories; with the Doctor having been filled with guilt over accidentally killing the race himself while trying to rescue a Lurman colony, Omega happened to take on that guilt after taking some of the Doctor's biodata. The Doctor reasoned Omega had only incorporated it into the memories to "explain away" Vandekirian's betrayal, even implying Omega had not killed Vandekirian as well. The Doctor also reasoned that Omega may have encorporated the story because the founder wanted to believe his exile had a cause, something to blame like an act of genocide, instead of merely being the result of a mistake. As for why Vandekirian betrayed Omega, the Doctor assumed he had indeed either sabotaged the mission on behalf of Rassilon, or he had just succumbed to madness. (AUDIO: Omega)

Although Rassilon publicly wept over Omega's death, (PROSE: Lungbarrow) the Eleventh Doctor appeared to believe the theory that Rassilon was behind the tragedy. Indeed, he later recounted to Alice Obiefune that it was rumoured Omega's "death" had been arranged, with those who spread the rumour claiming Rassilon had ordered "Omega's assistant" to betray the engineer. (COMIC: The Lost Dimension)

According to other accounts, a man known as "Fenris the Hellbringer" sabotaged Omega's Starbreaker. This nearly meant that the initial Gallifreyan time travel experiments never came to pass, so the Time Lords "[would] be annihilated before they [had] even come into existence". However, Rassilon intervened, dispatching Fenris; thus, although Omega was lost, the time experiments succeeded. According to this account, Rassilon prevented disaster from overtaking the other three Starbreakers (COMIC: Star Death) before weeping over Omega's death. (PROSE: Lungbarrow) Most accounts suggested that Fenris had been an agent for the Order of the Black Sun and acting deliberately, (COMIC: 4-D War) but according to one source, the man who caused Omega's death was a "temporal tourist" of no import, who had gone back to Gallifrey's ancient history to witness the historic moment of Qqaba's detonation. He was only given the melodramatic name of "Fenris the Hellbringer" in later retellings of the event, postdating his almost immediate obliteration by Rassilon. (PROSE: Gallifrey: A Rough Guide)

In yet another account, Omegon told K9 Mark I that he survived the event during which he granted the Gallifreyans the power to travel in time. Coasting on his fame and the debt he felt Gallifrey owed him, he had himself proclaimed Emperor. However, the other Time Lords plotted against him, and managed to depose him. They attempted to destroy him with the very "power of a thousand suns" he had harnessed for them, but they only succeeded in marooning him in a "crimson bubble of time", a time trap, from which they believed he could never escape. (PROSE: K9 and the Time Trap)

The survival of Omega
The Doctor, like most Gallifreyans, grew up to revere and admire Omega as their greatest hero. (TV: The Three Doctors) The Hand of Omega, meanwhile, had survived and returned to Gallifrey. The First Doctor would later obtain it for himself. (TV: Remembrance of the Daleks)

Omega had transported through the black hole into another universe made of anti-matter. Omega shaped the universe by force of will and access to the black hole's singularity. He could even create simple life. Radiation destroyed his body. The gauntlets, armour and helmet he had designed to protect him from the corrosive effect of the anti-matter now constituted his physical form. At first he shaped his new world into a paradise. As the centuries rolled by he grew weary and depressed, feeling abandoned by his fellow Time Lords. The landscape slowly transformed into a drab, grey desert as he became depressed by the loneliness he was feeling. The universe that had become his home was unstable, unable to exist without a powerful will to give it form; he was trapped and completely unable to escape. (TV: The Three Doctors)

Shortly after the early Time Lords abandoned the planet Minyos after setting themselves up as its gods, (TV: Underworld) Omega was able to psychically reach out to Oxirgi, a Minyan revolutionary, and form a psychic bond with him, with Oxirgi worshipping him in secret as his god. Under Omega's directions, Oxirgi created a matter converter which could open a gateway through the black hole, thus freeing Omega, if it was powered by a tremendous amount of negative psychic energy. To reach his target, Oxirgi had to create as much chaos and misery on Minyos as possible. When the suffering caused by the violent rioting Oxirgi organised failed to suffice, Omega suggested Oxirgi take control of the nuclear bombs left on Minyos by his people and destroy the planet. When Malika attempted to stop Oxirgi with the help of the mindwrangler Kyril, Omega poured more of his psychic power into Oxirgi's mind, helping him to fend off Kyril's psychic attacks. (COMIC: Omega)

A new plan
After thousands of years in the void, Omega hit upon a plan of revenge: a captured Time Lord could be forced to take his place, and Omega could leave and wreak vengeance on Gallifrey. This plan was inspired by the Verdigris, who had travelled into the anti-matter universe in an attempt to get the Third Doctor released from his exile on Earth. (PROSE: Verdigris) Using the black hole, he drained power from the Time Lords to stop them from interfering. He sent an amorphous life form and other, more humanoid servitors to find the exiled Third Doctor and take him into the black hole. The High Council, unable to send anyone to assist the Doctor, decided to have the second incarnation of the Doctor help rectify matters, subsequently contacting and sending his first self to advise them. Omega brought both incarnations to his domain, entry into which converted all matter into anti-matter. (TV: The Three Doctors)

Defeated by the Doctors
When Omega removed his helmet to prepare for his departure, he discovered that the anti-matter universe had completely dissolved his physical body. He could not leave his universe; he existed only because his will insisted that he exist, but his will was all that was left of him. Consumed by rage and despair, Omega swore to destroy all things; the dark side of his mind took the form of a demonic champion. The Doctors offered freedom to Omega: in actuality the Second Doctor's recorder which the Doctor's TARDIS had accidentally shielded from conversion into anti-matter. The Doctors attempted to trick Omega into touching the recorder but instead only infuriated him. When Omega lashed out he knocked the force field generator to the floor, causing the recorder to make contact with the floor and creating a violent matter-antimatter explosion which seemingly killed Omega by collapsing the antimatter world. (TV: The Three Doctors)

Assailing Gallifrey
Having survived his encounter with "K9's former master", Omegon plotted vengeance on the Time Lords. He learned how to capture spacecraft into his timeless realm; they appeared to disappear from the normal universe in a blink due to no real time existing inside his bubble of frozen, crimson time. A boundary between the bubble of time and the normal universe now existed in the form of a cloud of reddish cosmic gas, seemingly intangible, whose movements Omegon could direct from the inside; he thus intended to move the cloud nearer to Gallifrey once he had collected a big enough fleet, and launch a surprise assault on the planet, intent on wiping out the Time Lords altogether.

Among the spacecraft he thus highjacked was the entire Rigelian Seventh Fleet, the disappearance of which was investigated by K9 Mark I on behalf of Gallifrey High Command. When K9 managed to enter Omegon's realm, he personally greeted him, explaining his history to K9 and trying to convince the hound that his actions were justified. However, K9, deeming that Omegon was mad with revenge, managed to retake control of his own spacecraft, the K-NEL, launching it at the rocket stores of Omegon's flagship just as the invisible fleet was nearing Gallifrey. The flagship was destroyed in a colossal explosion which seemingly killed Omegon, freeing the captured ship from his control. (PROSE: K9 and the Time Trap)

Affiliation with the Arc of Infinity
Hedin of the High Council contacted Omega to help him. Omega had gained control of the dimensional gateway known as the Arc of Infinity. Through the Arc, he had a gateway between his own universe and the universe of matter, though he still had no physical form. Omega also had a TARDIS and a servant he had created, the Ergon. Omega needed to bond with another Time Lord using his biodata extract. (TV: Arc of Infinity)

On Earth at the time, Omega sent the Ergon to survey the planet, and it ended up in Perivale, where it met Dorothy McShane working in a fast food restaurant. She didn't realise it was an alien, and gave it some fries, which it took back to Omega. Omega didn't like them, claiming they didn't have any salt on them. (PROSE: Anti-Matter with Fries)

Hedin transmitted to Omega the biodata extract for the Doctor, by this time in his fifth incarnation. Omega established a base in the Earth city of Amsterdam, navigated the Doctor's TARDIS into the Arc and began to link the Doctor's biodata with his own. The Doctor faced execution on Gallifrey to stop Omega's return. This was part of Omega and Hedin's plan: they rigged the execution to hide the Doctor and Omega in the Matrix, safe from Time Lord detection. (TV: Arc of Infinity)

A new body
Omega shifted the Arc to Gallifrey in order to gain control of the Matrix and used its power to create a physical body for himself.

The Doctor tracked him down and sabotaged his equipment in Amsterdam, forcing Omega to step into the physical universe before the transfer was made stable. His new body, a replica of the Doctor's, began to decay and revert to anti-matter. Thwarted and maddened by defeat, Omega willed the acceleration of his conversion to anti-matter to destroy the Earth rather than return to the universe of anti-matter but was destroyed by the Doctor using the Ergon's matter converter. (TV: Arc of Infinity)

After Amsterdam
Omega was recreated by using the Doctor's biodata. However, this had the effect of causing Omega to develop a split personality, being both Omega and the Doctor, but the Doctor persona wasn't aware of his Omega personality. In Amsterdam, Omega secretly boarded the TARDIS of a visiting Time Lord historian and broadcaster, Professor Ertikus, who was in the city to see the site of Omega's destruction. Ertikus travelled to a Jolly Chronolidays trip to the Sector of Forgotten Souls, with Omega stowed away onboard. Before the trip, Omega met an employee of Jolly Chronolidays, Sentia, with whom he fell in love. He told Sentia all about himself, including his split personality disorder. Omega planned to use the Jolly Chronolidays trip to the Sector of Forgotten Souls to return to the anti-matter universe with Sentia because he found he disliked living in this universe, and wanted to return to his universe where he had godlike power and remained safe.

While travelling to the Sector of Forgotten Souls, the Doctor persona met Sentia for the first time (although Sentia already knew about this Doctor personality) while the ship was docking into the leisure base. There he met Daland (an actor who played Omega in the recreations of Omega's experiments) and Tarpov (another actor who played Vandekirian, Omega's assistant). Tarpov succumbed to the Vandekirian personality, left behind by the psychic residue from Omega's experiments. He tried to stop Omega's experiments by attacking Daland and crushing his own hand in machinery, to stop his handprint being used to release the Hand of Omega, but Omega entered and stopped Tarpov from crushing his other hand. While Tarpov was recovering, Omega tried to kill Tarpov, believing he would give away a secret that he wished to keep quiet, but the medical robot knocked him unconscious. The Omega persona directly communicated with the Doctor persona inside Omega's mind. "Omega" tried to convince "the Doctor" to help him travel to the anti-matter universe with Sentia, and "the Doctor" accepted. Meeting Ertikus for the first time, and discovering he was a Time Lord, "the Doctor" used Ertikus' TARDIS to travel to the recreated Eurydice so he could fulfil his mission. But Sentia kidnapped Daland and stole a shuttle, so she could get there, and could use Daland to conduct the marriage ceremony, but Tarpov stowed aboard and escaped onto the Eurydice.

Tarpov revealed to Sentia that by destroying a star, to create the Eye of Harmony, he would cause the death of a native race called the Scintillans, however, Omega continued anyway. Omega then killed Tarpov. Ertikus tried to meet Omega but discovered that "the Doctor" had been in contact with him all along. Omega revealed himself to Ertikus and then killed him. After they were reunited, "the Doctor" sent a telepathic message from Ertikus' telepathic circuit to the Time Lords explaining everything about the situation to them, so they could send help. Daland and Sentia looked for Ertikus, and Daland found his recorder robot, which had recorded Ertikus' death. Daland realised that "the Doctor" had killed him, and tried to attack the Doctor. Seeing the footage for himself, "the Doctor" realised he was merely a product of Omega's split personality disorder, which was finally confirmed by the arrival of the real Fifth Doctor in his TARDIS, who had been sent by the Time Lords.

Feeling the effects of mental trauma, Omega escaped and began to suffer flashbacks of his earlier life, and the circumstances which lead him to take part in the time experiments. After hearing about the Scintillans from Daland, the Doctor confronted Omega, and revealed that the Scintillans weren't a part of the time experiments, but a memory Omega had taken from the Doctor. The Scintillans were a species the Doctor accidentally killed when he tried to save some Lurmans. The Doctor believed Omega had subconsciously used this to explain away Vandekirian's betrayal. Sentia (taken over by Vandekirian's personality) attempted to pilot the Eurydice into the anti-matter universe, so Omega would be trapped again. The Doctor and Daland escaped, while Omega was trapped on the ship, as it and Omega were supposedly pulled back into the anti-matter universe again. (AUDIO: Omega)

Return
For centuries on Gallifrey, the Adherents of Ohm were a secret society that worshipped "Ohm", (AUDIO: Intervention Earth) a name for Omega used by those who believed him to be a "trapped god". In another universe, Savar met "Ohm" within a black hole. (PROSE: The Infinity Doctors)

Omega manipulated the Adherents of Ohm to steal the Hand of Omega from Gallifrey and use it to create a black hole. Omega then lured Tauras and brought him and Ace's TARDIS into the anti-matter universe. When he met Romana he thought the Time Lords society had fallen so low to allow a president from the House of Heartshaven. Possessing Tauras' body, Omega took Ace's TARDIS and escaped the anti-matter universe, knowing that it would allow him back on Gallifrey as it was known to the Celestial Intervention Agency. (AUDIO: Intervention Earth) Romana sent Irving Braxiatel back in time to change history so that Omega would never escape the anti-matter universe. (AUDIO: Enemy Lines)

Personality
While there was a time when he opposed violence and only wanted to be known by his birth name, he came to believe that, if he needed to be a monster to bring the Gallifreyans into a "new age of enlightenment", then he would fully become said monster. He also came to begrudgingly accept his nickname "Omega". (AUDIO: Omega) Omega was very bitter about his fellow Time Lords, who he believed sacrificed him to attain greatness. He held eternal enmity towards his race, and sought to avenge himself against them.

Countless aeons alone left him with little care about anything, deeming the destruction of reality as a "spectacle to behold". He also became paranoid and developed violent mood swings. He lacked any restraint and had a vicious temper. The Doctor considered him to be a madman. However, he was not without heart, and appeared enchanted by small things such as a child's smile and a steam organ during his brief escape from the anti-matter universe, suggesting that his extreme fury was merely the by-product of loneliness and despair. (TV: The Three Doctors, Arc of Infinity)

Despite being insane, Omega was noted for his extremely strong will, which allowed him to reshape the antimatter universe in the singularity to create an environment as well as servants that suited him. This made him linked to the antimatter realm, as his will alone kept it alive and prevented his escape. He was completely unaware of the fact that his body had corroded away as a result of prolonged exposure to the antimatter realm, and that both his physical form and the world he created were made by his will alone. (TV: The Three Doctors)

In Time Lord culture
Rassilon, the Other and Omega were the three most important figures in Gallifrey's history. (PROSE: The Ancestor Cell) An ancient Statue of Omega was in the Capitol, (COMIC: The Lost Dimension) whereas another was built in the Great Hall of the Academy during his life. (AUDIO: Omega)

The Feast of Omega was a holiday that was celebrated on Gallifrey. (PROSE: Happy Endings) It was the Disciples of Omega who established the transduction barriers. (AUDIO: Renaissance) The public forgot that Omega's birth name had been Peylix, with the name instead becoming the subject of a story about a time plumber who questioned how everything worked, which made everything stop working. (AUDIO: Omega)

The Belt of Omega was part of a Presidential dress which the Fifth Doctor was forced to wear. Seeing him fit it on, Tegan Jovanka amusingly suggested that Omega had tried to steal his body because he was jealous. (AUDIO: Time in Office, TV: Arc of Infinity)

"OMEGA level event and "Priority Omega" were code-phrases during the War in Heaven and Last Great Time War, respectively. (PROSE: Subjective Interlock, TV: The Day of the Doctor) The Omega Arsenal was a stockpile of forbidden weapons locked away in the Time Vaults. (TV: The Day of the Doctor)

Secret societies on Gallifrey were dedicated to the worship of Rassilon, Omega, and the Other. The Adherents of Ohm were one dedicated to Omega, (AUDIO: Intervention Earth) with "Ohm" being a name for Omega used by those who believed him to be a trapped god. (PROSE: The Infinity Doctors) By the time of his fifth incarnation, the Doctor's battles with Omega had turned Gallifreyan culture against the founder, having revealed many of the unfavorable aspects to Omega's character; Omega went from a revered founder to a story used to scare children into doing homework. By the time of the Celestial Preservation Agency, Omega was no longer seen as a hero, merely considered a joke. (AUDIO: Omega)

Coordinator Jarad was once heard to exclaim "Omega's ghost!" to express shock. (AUDIO: Legion of the Lost) In a parallel universe where the Sixth Doctor led Gallifrey in the War, a time dreadnought was named the Glorious Aspect of Omega. (PROSE: The Quantum Archangel)

Other references
In the video game Happy Deathday, played by Izzy Sinclair on the Time-Space Visualiser, Omega was among a host of "every single enemy" that the Doctor had ever defeated, who were assembled by the Beige Guardian and pitted against the Doctor's first eight incarnations. (COMIC: Happy Deathday)

During the War in Heaven, the term "OMEGA level event" was used to describe direct encounters with The Enemy. (PROSE: Subjective Interlock) During the Last Great Time War, Priority Omega was a code phrase used for high priority messages. (TV: The Day of the Doctor)

Development
In preliminary discussions for The Three Doctors, the name "Ohm" was considered for the character of Omega, because OHM looks like WHO upside-down. The symbol for Ohm is the Greek Omega symbol (Ω). This abandoned concept would be referenced in the novel The Infinity Doctors, where, within an abnormal state of history, it was revealed that the Time Lord explorer Savar met a "mad god" called Ohm inside a black hole while looking for the real Omega. The suggestion is that Ohm is one of an infinity of alternative versions of Omega. In K9 and the Time Trap, Omega was referred to with the name "Omegon", otherwise remaining identical to the version of the character seen in The Three Doctors, evidencing lingering uncertainty in the mind of his creator about Omega's name.

In The Three Doctors, Stephen Thorne, who had previously portrayed another vengeful near-deity (the Dæmon Azal) in The Dæmons, was called upon to portray Omega. With the character meant to have no physical body under his helmet, only Thorne's voice was applied to Omega, thus allowing for easy recasting upon Omega's return to the series in Arc of Infinity. The anti-matter god was now embodied and voiced by Ian Collier, who reprised the role in an audio format in the Big Finish audio drama Omega.

In the scene corresponding to the point in The Timeless Children where Tecteun's male incarnation stands alongside two other Time Lords in full high-collared regalia, the Timeless Children script release mentions that "we can assume [the other two] are Rassilon and Omega". In late 2020, the BBC released a promotional photograph providing a better look at these Time Lords' faces. Mark Corden, the episode's 2nd assistant director, claimed on Twitter that he himself was the performer playing "Omega", also explaining that he had selected the extra playing Rassilon based on his resemblance to Don Warrington, who had played an incarnation of Rassilon for Big Finish.

John Ridgway, the artist for Cutaway Comics' Omega miniseries, elaborated in a special feature at the end of the first issue on an early concept he had when called upon to visualise Omega in the comic: "You can't have him be a little man like the Mekon. It has to be dynamic, fluid, and fit in with the script. My original thought, which sadly won't work, is he'd be different every time that you saw him. He could be male in one picture, Chinese in the next, female in the next and all the permutations of that. But the readers would need to understand this is what was happening, without wondering why there were so many different characters."

- John Ridgway

In the end, Omega was depicted in Oxirgi's vision as a hazy humanoid figure seemingly made of pure light — thus obviating the need to give him any particular physical features.

In invalid sources
Omega appeared as the antagonist of Search for the Doctor, a novel which is not considered a valid source on this Wiki due to being a "Choose Your Own Adventure"-style multiple-choice narrative. The illustrations depicted Omega using an all-new design for his helmet, distinct both from the one in The Three Doctors and the one in Arc of Infinity.

Other matters
A character called "Rassilon's Engineer" appears in a transmission Sam Jones receives on Anathema in Interference - Book One. Although the character is not named, he is strongly implied to be Omega. The transmission originates in a Faction Paradox-influenced culture built on a Time Lord artefact, so the implication may be that Rassilon attempted to minimise Omega's part in Time Lord history, reducing him to the role of "Rassilon's Engineer".