To unlock the Fourside stage, you must play at least 100 matches in VS. To unlock the Flat Zone stage, you must complete 1-P Classic mode at any difficulty/stock with Mr. To unlock the Final Destination stage, you must complete all 51 Event Matches. To unlock the Dream Land stage of the past, beat Target Test with all characters, regular and hidden. To unlock the Brinstar Depths stage, you must play at least 50 matches in VS. To unlock the Big Blue stage, you must play at least 150 matches in VS. To unlock the Battlefield stage, complete the All-Star 1-P mode for the first time. You'll then be challenged by Young Link defeat him. Young Link: To unlock Young Link, complete Classic mode with 10 different characters at any difficulty/stock. Roy will challenge you defeat him and you can play as him. Roy: To unlock Roy, complete Classic Mode using Marth at any difficulty/stock. Pichu will challenge you win and you'll be able to play as Pichu! Pichu: To unlock Pichu, complete Event 37 (Legendary Pokémon). After you do that, you'll be challenged win this battle. Game & Watch, you must complete both Classic and Adventure 1-P mode or the Target Test with ALL characters at any difficulty/stock, regular and hidden that includes Mewtwo. After either requirement is met, Mewtwo will challenge you beat him.