The Nintendo 64 Expansion Pak was used in conjunction with certain games to allow for enhanced gameplay. Donkey Kong 64 and The Legend of Zelda: Majora's Mask required the Expansion Pak for gameplay, whereas games such as Hydro Thunder and Perfect Dark used it to unlock multiplayer and other features. Re-Volt, Road Rash 64, and other games used the Expansion Pak to unlock higher resolutions.