Roy is the main character in Fire Emblem: Fuuin no Tsurugi, the first entry in the series to appear on the Game Boy Advance. He is the son of Eliwood, making him the heir to the title of Marquess of Pherae. The identity of Roy's mother is not revealed in the game, but in the following Fire Emblem, Eliwood may end the game by marrying either Lyndis, Ninian, or Fiora, making all three of them his potential mother. Regardless, it is implied that Roy's mother died of illness when he was young.
Roy is the sole Lord character and protagonist of Fuuin no Tsurugi. In the typical tradition of Fire Emblem's Lords, he starts with somewhat shaky base stats, but soon grows into a high-performance unit. He reaches his secondary class very late in the game, with only four chapters left to go. His promotion to the Master Lord class is triggered, story-wise, by him inserting the Fire Emblem into the hilt and thereby unlocking the Sword of Seals from Shrine of Seals in Bern, and then subsequently drawing the blade.
Roy is only fifteen years old when the story of Fuuin no Tsurugi begins. Bern had recently conquered the neighboring nations of Sacae (a vast plains country inhabited by mounted nomadic warriors) and Ilia (an arctic, barren nation famous for its skilled and devoted mercenaries), and had turned its sights to the Lycian League. Following the Lycian code, each province is obligated to send their armies into battle against those who would attack the nation-states; Roy is thus called home from his studies in Ostia to lead Pherae's armies in his ill father's stead.
Along the way to Araphen (the Lycian realm closest to Bern), he meets the errant princess of Bern and sister of King Zephiel, Guinevere, who had escaped from her land in the hopes of negotiating a treaty with Lycian nobility. Roy quickly agrees to her proposal to search for a peaceful means to end Bern’s aggression. This encounter, followed by his tardy arrival at Araphen to a dying Lord Hector, eventually leads him on a journey across Elibe to save the continent from another war between dragons and humans. Roy also swears an oath to Hector in Chapter 3, in which he promises to protect Lilina, Hector's daughter.
Roy is an upstanding, thoughtful, and idealistic young man who repeatedly shows a desire to help and support others, shown in his interactions with Guinevere and Lilina. While he would prefer to avoid bloodshed – a fact reflected in his interactions with Guinevere and his tactical efforts to conserve his soldiers – he maintains a strong resolve to see peace return to Elibe. Roy is also perceptive and cunning for his age; he tricks a traitorous Lycian vassal into exposing himself, discerns that the bard Elphin (who is in reality the missing Etrurian Prince Mildain) is more than he seems, and often reacts calmly and tactically to disturbing news.
Despite his tactical prowess, Roy is also quite oblivious to the obvious feelings that some of the women in the army develop for him, as demonstrated most often in his support conversations. Lilina in particular is quite smitten with him regardless of the player’s actions, but he never notices this. Depending on the support route taken, Roy can either marry Lilina, the Sacaean nomad Sue, the dancer Lalam, the valkyrie Cecilia, the Pegasus Knight Thany, or the Shaman Sophia. Each route presents Roy with a different ending.
In the Super Smash Bros. Series
Roy is an unlockable character in Super Smash Bros. Melee, and one of two characters from the series to appear in the game. His inclusion on the roster was meant to serve as promotion for Fuuin no Tsurugi. Incidentally, Super Smash Bros. Melee was released before his debut in the Fire Emblem series in all regions making Melee his technical first appearance. Roy's moveset is largely taken from Marth, with modified stats and effects. He is not a playable character in Super Smash Bros. Brawl, but he is featured as a sticker. Data in the game indicates that he had been planned as a playable character during development, but was dropped.
Fire Emblem: Awakening
Roy makes an appearance in Fire Emblem: Awakening in the 2nd round, Another Story: Spirit Talisman 2. He is available if the player has bought Spirit Talisman 1, and Roy is available as a party member for 250 Yen. His artwork is done by Kimihiko Fujisaka.