Players begin the game with a selection of cards that offer different actions during key situations. Over 200 cards can be collected, and allow Snake to sneak around the island, take out guards and reach his targets. As with previous Metal Gear titles, Metal Gear Acid is packed with plot twists, while the gameplay constantly evolves as further cards and abilities become available. The many cards Metal Gear Acid offers give Snake a wealth of offensive possibilities, weapons and characters, while different decks allow for themed missions unique to each collection, further expanding the challenge.

Each of the cards and its attributes are fully detailed in the lavish 20-page booklet. The book as been designed by the development team to assist players as they explore Lobito Island, and give prior knowledge of cards as they are collected. It will also make the formulation of strategies easier as players will know the various strengths and weaknesses of the moves and weapons at Snake’s disposal.