"He said, we are both damned."
"Well, it's a small enough price to pay for immortality."
- – Londo Mollari and Antono Refa
Lord Antono Refa was extremely ambitious and ruthless in his efforts to increase his personal power and influence, and was willing to instigate mass murder, assassination and outright betrayal to achieve his goals. Preferring to operate behind the scenes and manipulate others to serve his needs, he rarely moved directly or risked his own neck unless he was sure of success. Like many noble Centauri of the old school of thinking, Refa considered his race to be superior while other races, especially the Narn, were to him little more than animals and had no qualms against committing war crimes, mass destruction or outright genocide against them if it suited his aims.
Refa's ultimate ambition was nothing less than claiming the Imperial Throne for himself. Initially Refa saw Londo Mollari as an ally and worked together with him in their mutual desire to restore the Centauri Republic to its former power, prestige, and glory. However, as their alliance became increasingly uneasy, they became bitter rivals.
The Imperial Coup
Refa appears on Babylon 5 shortly after the only son of Emperor Turhan dies, leaving a gap in the line of succession for the Centauri throne. On his first visit, Refa makes it clear to Centauri Ambassador Londo Mollari that he speaks for a group of Centauri politicians who are interested in making a move for the throne after the death of Turhan. Given Londo's newfound prestige in the Royal Court, which he gained following military successes brought about by his clandestine dealings with Mr. Morden, Refa comes to Londo to ask for his support in the group's plans. Londo gives his consent, a decision that would set him on a course with the destiny he always foresaw.
Later, this group stages a coup while the ailing Turhan pays a visit to Babylon 5. The purpose of this visit, as Turhan sees it, is to ask for forgiveness and peace from the Narn ambassador, G'Kar, for the great abuses the Centauri had done to the Narn. Unfortunately, Turhan collapses before he can make this offer in person to G'Kar, though his message is relayed to G'Kar through Dr. Franklin. With Turhan now dying and his message of peace not delivered in public view of the Centauri and Narn, Refa's men take this opportunity to strike, ordering the assassination of Turhan's prime minister on Centauri Prime, while Refa and Londo, on Babylon 5, are present at the death of the Emperor. 
The Narn-Centauri Conflict
With his political enemies out of the way, Refa and his associates install the mad Cartagia as Emperor, and begin a protracted war against the Narn. Utilizing Londo's agreement with the Shadows and Centauri forces, Refa personally oversees the war. In the end, learning of the news that the Narn plan to use virtually their entire fleet to attack a Centauri supply post, he decides to launch an assault on the Narn homeworld.
Refa cannot do so without Londo's help, however, and though Londo reluctantly agrees, he asserts that this is the last time he will bring his associates into the situation. Soon after, the Shadows are unleashed on the Narn fleet, obliterating it, while the Centauri fleet, making use of banned planetary bombardment weapons called mass drivers, attacks and subjugates Narn, under the observation of Refa, Londo, and their Centauri allies. 
The Shadow War
After this victory, Londo informs Morden that he will no longer be in need of assistance from his associates, which prompts Morden to begin contact with Lord Refa. When Morden informs Londo of this, Londo becomes quite concerned. In an effort to prevent Lord Refa from continuing his relationship with the Shadows, Londo "poisons" Refa's drink during a meeting on Babylon 5. Telling him that it is a two-stage poison that will not kill him until the second part is introduced, Londo assures Refa that this second part will not be introduced now if contact with Morden is ended, but it still may happen in the future should Refa betray him. An angry Refa realizes that Londo has him, and breaks off the contact with Morden.
Again, Morden comes to Londo, this time quite angry that Londo would interfere in his associates' activities in this way. However, Londo really wants nothing more to do with Morden, so when Londo gives him the brush off, Morden arranges for Londo to care again, by setting up the murder of Londo's true love, Adira Tyree. However, Morden takes this further, by poisoning her with a poison of Centauri origin, allowing Morden to convince Londo to place the blame on Lord Refa, whom Londo already knows is still upset about being "poisoned." This, again, places Londo in association with Morden. Finally, though, Londo resolves to do something about Lord Refa, who has himself been inciting a feud between their two houses on Centauri Prime. 
In an elaborate plot staged to maximize Londo's political gain, Refa is lured to the Narn homeworld in expectations of capturing G'Kar, who is on Narn ostensibly looking for his old assistant, Na'Toth. However, the actual plan is to capture Refa, who was responsible for the decision to use mass drivers on Narn, and turn him over to G'Kar and members of the Narn Resistance who were allowed by Londo to kill this Centauri without retaliation. Two of the reasons Londo had for having Refa killed were personal: the death of Adira (though Refa was not actually involved in) and the deaths of Urza Jaddo (which Refa brought about) and Prime Minister Malachi. In the end Lord Refa is surrounded by G'Kar's Narn associates and beaten to death for his involvement in the bombing of the Narn homeworld and the installation of death camps and genetic cleansing programs. Mollari also arranged for the liberation of two thousand Narn in exchange for Refa's death. On Babylon 5, Londo presents evidence of Refa's "betrayal" against the Republic and personal plots to a visiting Centauri minister, gaining prestige in the royal court and ruining Refa's name. 
- Refa's accent (and by extension Londo, and Urza's) is characteristic of Centauri Prime's northern province and is generally indicative of the "old school" of court nobility.
- Babylon 5
- The Coming of Shadows
- Ceremonies of Light and Dark
- Interludes and Examinations (flashback)
- And the Rock Cried Out, No Hiding Place