A 2020 Military Science Fiction work by Joe Kassabian, and the second installment in the "Galaxy on Fire" series and the sequel to Citizen of Earth. Nineteen year-old Vincent Solaris is a long way from his government-issued home in Detroit District Six. Having survived multiple alien battlefields more through luck than skill, Vincent has found himself named the Cohort Leader of the Elysian Humans, a ragtag collection of Earth Defense Force survivors from the Battle of Grawluck who have been taken in by the Fidayi after the destruction of Earth. Most of the Fidayi leadership give Vincent little respect. Most of the Elysian humans give him even less. And that doesn't even count the Black Coats, fanatical devotees to the deceased Chairman, who have dubbed Vincent "The Great Traitor" and blamed him for the destruction of Earth.
With the Fidayi hard-pressed to press their counter-attack against a still very strong Alliance, many question why they waste resources supporting the human refugees. Meanwhile, Vincent argues for the chance to allow the Elysian humans to fight alongside the Fidayi and earn their keep, but the Warlord and her cohort leaders are hesitant to arm their recent enemies, even against a common foe. With the Black Coats becoming more and more violent, Vincent and Fiona form a militia to try and keep the peace in the Human Quarter, which leads to open warfare breaking out between the two factions.
Soon, they learn the situation is worse than they thought. The Committee survived the destruction of Earth, leading from their new capital of Lunar City, and Vincent is dispatched to the human colony of Titan to convince them to join the Fidayi in breaking the Committee's back by liberating Mars. If Vincent thought he hard a hard time getting people to work together on Elysian, he will soon learn that things are much more difficult on war-ravaged Mars, with rival gangs more interested in one-upping each other and protecting their petty fiefdoms than in uniting against the Earth Defense Forces. To say nothing of the Titanians' intent for the planet.
The Great Traitor provides examples of:
- Ace Pilot: Lieutenant Colonel Ezra Vorbeck, a Titanian officer and convicted soldier who offers his services as a gunship pilot when he learns Vincent is trying to raise an army.
- Action Survivor: It's not that Vincent is particularly badass, so much as he possesses some basic soldiering skills and enough luck to survive numerous near-death experiences.
- Back for the Dead: Ezra's copilot and nominal boss, Nox, dies early in the book.
- Battle Couple: In addition to Vincent and Fiona, this book introduces Ezra Vorbeck and Anastasia Tirpitz, unfortunately, that ends with Tirpitz's death in a Martian ganger ambush.
- The Cavalry: The Fidayi forces rush to attack Victoria after Denta and Erik's forces are ambushed there. Similarly, when Vincent's forces get bogged down trying to breach the defenses, they are saved by the timely intervention of Arai's armored column.
- Communications Officer: Captain Anastasia Tirpitz is a Titanian Pathfinder, trained to call in air and orbital strikes on enemy positions. Later on, Lieutenant Felicity Haagen, Vincent's aide, has a radio set which she uses to help him talk to other commanders and call in fire missions.
- Dark and Troubled Past: Fiona's youth was worse than she previously let on. She wasn't a ganger who got drafted, but instead a sex slave who joined the EDF to escape her abuser.
- Defensive Feint Trap: Denta and Erik are lured into an ambush at Victoria when Brusilov's defenses seemingly collapse, drawing them deep into the city's interior.
- Does This Remind You of Anything?: The Black Coats, fanatical (and very racist) devotees to The Chairman bear more than a passing similarity to the Brownshirts.
- Death from Above: Artillery, air strikes, and Orbital Bombardment all feature in the fighting on Mars. As well as the climactic destruction of Victoria.
- Embarrassing Nickname: Vincent is not overly fond of being called "The Great Traitor." So naturally his own forces insist on referring to him by that, going so far as to use it as his radio callsign on the battlefield.
- Enemy Mine: The Fidayi, Titanians, and three rival Martian gangs have at least as many reasons to distrust each other as they do reasons to fight against the Earth Defense Forces. Later in the Martian campaign, thousands of Earth Defense Force deserters join them, in hopes of escaping the Black Coats.
- Godzilla Threshold: Faced with the prospect of spending months in brutal street fighting against Brusilov's forces, while facing the very real danger of being attacked by reinforcements from Earth or a new Alliance offensive, Vincent, Denta, and Erik agree to withdraw and level the city from orbit.
- Hyper-Competent Sidekick: Late in the book, it is agreed that Vincent needs an Aide to help him keep up with his administrative duties, and he ends up with Felicity Haagen, a nervous young Lieutenant fresh from the Titanian Military Academy.
- Red Baron: Vincent Solaris, The Great Traitor, as well as the book's villain, Brusilov the Butcher.
- Reports of My Death Were Greatly Exaggerated: Vincent is briefly believed to have been killed during the Fidayi assault on Victoria. The same is true of Arai.
- You Are in Command Now: More than a few of Vincent's commanders happen to be noncommissioned officers who proved themselves to be brave, reliable, and lucky enough to survive the fighting. And then Vincent ends up in command of the Fidayi forces during their attack on Victoria after Arai's ship is shot down, though she is later revealed to have survived.
