Instructions
Enter "Vs Mode" from the main menu of "Super Smash Bros. Brawl."
Choose one of the fourteen starting characters to use in the round. Play one round in "Vs Mode" with the character and return to the "Character Select" screen.
Choose a different character to play as in the next round. Repeat until you have completed one "Vs Mode" round with each of the fourteen characters. You will then be challenged by Marth.
Defeat Marth by knocking him off the stage to unlock him as a playable character in the game.
Return to the main menu and select ̶0;Classic Mode.̶1; Choose Marth as your character and set the game difficulty at ̶0;Easy.̶1;
Play through Classic mode with Marth and do not use any continues. After the credits you will be challenged to a duel against Roy.
Defeat Roy by using Marth's Dragon Slayer move, pressing ̶0;Forward̶1; and ̶0;A̶1; on your controller when near him. Once defeated Roy will be unlocked and you can play as him in any game mode.