Roy is the protagonist of Fire Emblem: Fūin no Tsurugi (Binding Blade) and the son of Eliwood, the main character of Fire Emblem: Rekka no Ken.
Roy's mother could be either Lyndis, Fiora, Ninian, or a nameless woman, depending on who Eliwood gained supports with in Rekka no Ken or if he had any supports at all. Roy is also given access to the Sword of Seals, one of the most powerful weapons in Fūin no Tsurugi. He is stated in the Hasha no Tsurugi manga to be 15 years old.
He makes a brief cameo in the ending to Rekka no Ken.
Fire Emblem: Awakening
Roy reappears in two different forms, as a SpotPass character in the base game and a DLC Einherjar unit.
Super Smash Bros. series.
Super Smash Bros. Melee
Roy appears as a playable character in Super Smash Bros. Melee. He can be unlocked by completing either Classic or Adventure Mode as Marth on any difficulty without using continues, or by playing 900 Vs. Matches, he then must be defeated on the Temple stage in order to be unlocked. Roy debuted in this game before appearing in his home franchise.
Super Smash Bros. Brawl
Roy did not return in Super Smash Bros. Brawl as a playable character, but music associated with the character, "Winning Road - Roy's Hope", including data for a character slot, is present in the game. Roy also appears as a sticker.
Super Smash Bros. for Nintendo 3DS/Wii U
After being absent in Brawl, Roy returns in Super Smash Bros. 4 as a playable DLC character. Marth has a alternate costume that resembles Roy's outfit from Melee. Another Roy also appears as an unrelated new character. Music associated with the character, "Winning Road - Roy's Hope", is also present in the game.
Before becoming a DLC character for SSB4, sound files for Roy's victory theme were found in the 1.0.6 update.