Metal Gear Ac!d — Before each round, the player can customize the deck of cards that the main characters use. Most of the cards are based on elements spanning the entire Metal Gear series, such as weapons, characters, and even Metal Gear itself. At the beginning of the game, a player's hand can consist of a maximum of six cards. The maximum number of cards in the deck increases with overall progress. In action mode, the player can use the cards for their intended purpose or use them to move the character. Most cards only allow the player to move three spaces, while some cards allow the player to move six or more spaces.