Spawn medpak: Press Up(2), Down(2), Left, Right, Left, Right, B, A during game play. Spawn ammunition cartridge for current weapon: Press Y, B, A, X, White, Y, X, A, B, White during game play. Chapter select: Press Left(4), Black, Right(4), White during game play. Return to the main menu and start a new game to have all chapters unlocked.