The first Metal Gear Acid for the PSP added new turn-based gameplay to the Metal Gear franchise, and its sequel brings more of the same. Metal Gear Solid 2 is another hybrid action-battle-card game that lets you play as the highly trained special agent Solid Snake. Metal Gear Acid 2 provides more than 500 battle cards, new characters, a new “Metal Gear,” and a revamped interface. It’s also compatible with the new 3D goggle attachment for the PSP.