Go to the last character in multiplayer mode and press:

                                    hold L+R and press <C
                                    hold L and press ^C
                                    hold L+R and press < on the control pad
                                    hold L and press > on the control pad
                                    hold R and press \/ on the control pad
                                    hold L+R and press <C
                                    hold L and press ^C
                                    hold L+R and > on the control pad
                                    hold L+R and press \/C
                                    hold L and press \/ on the control pad

           Other Cheats
 

        Level                              Difficulty                           Cheat

        Dam                                00 Agent                           Paintball mode

        Facility                            00 Agent                            Invincibility

        Runway                            Agent                               DK mode

        Surface 1                        00 Agent                            ????

        Bunker 1                           Agent                              2X Throwing knives

        Silo                                 Secret Agent                      Turbo mode

        Frigate                            00 Agent                            No radar

        Surface 2                        00 Agent                            ????

        Bunker 2                        00 Agent                             ????

        Park                               00 Agent                            Fast animation

        Archives                        00 Agent                             Invisibility

        Streets                             Agent                                Enemy Rockets

        Depot                            00 Agent                            Slow animation

        Train                            00 Agent                            silver PP7

        Jungle                            Agent                                2X Hunting Knives

        Control                           Secret Agent                       Infinite Ammo

        Caverns                        ????                                    ????

        Cradle                            00 Agent                            gold PP7

        Aztec                            00 Agent                            2XLasers

        Egyptian                        00 Agent                            All Weapons