Metal Gear Acid 2 (rendered METAL GEAR AC!D² on the official logo, abbreviated MGA2) is a video game developed by Kojima Productions and published by Konami for the PlayStation Portable. As the sequel to Metal Gear Acid, it establishes the Acid games a separate franchise from the main Metal Gear Solid series. MGA2 uses the same turn-based strategy and trading card-based system as the original MGA. The presence of a superscripted "2" next to the game's logo is a reference to the upgradable card system, resulting in more than twice the number of cards than the original game. As from the first game, ACID stands for "Active Command Intelligence Duel."