DK mode is obtainable by finishing Chicago Stealth on Agent setting.
Slow motion one player is obtainable by finishing DataDyne Research Investigation on Agent setting.
Small character mode is obtainable by finishing Area 51.
To get a new Title screen and secret level finish the game on agent setting and you get a new title screen and one of four secret levels called Mr. Blondes Revenge where you get to play as Mr. Blonde.
to unlock the psychosis gun finish chicago-stealth onperfect agent in under 2 minutes.
Use the psychosis gun on an enemy especially one with an impressive array of weapons and he will join your side and shoot any of your enemies.
In challenge mode to unlock these options in combat simulator:
| NAME | CHALLENGE NUMBER |
| DataDyne SECURITY GUARD | 5 |
| OFFICE SUIT | 6 |
| OFFICE CASUAL | 6 |
| JOANNA NEGOTIATOR | 8 |
| NEGOTIATOR | 8 |
| DataDyne SNIPER | 8 |
| TRENT EASTON | 9 |
| NSA LACKEY | 9 |
| JOANNA LEATHER | 10 |
| G5 GUARD | 10 |
| G5 SWAT GUARD | 10 |
| MR. BLONDE | 11 |
| DINNER JACKET (WHITE) | 11 |
| DINNER JACKET (BLACK) | 11 |
| DINNER JACKET (UNBUTTONED) | 11 |
| DINNER JACKET | 11 |
| JOANNA TRENCH COAT | 12 |
| CIA AGENT | 13 |
| FBI AGENT | 13 |
| JOANNA LAB TECH | 14 |
| AREA 51 GUARD | 14 |
| AREA 51 TROOPER | 14 |
| PILOT | 14 |
| OVERALLS | 14 |
| MALE LAB TECHNICIAN | 15 |
| FEMALE LAB TECHNICIAN | 15 |
| DataDyne LAB TECHNICIAN | 15 |
| BIOTECHNICIAN | 16 |
| ELVIS | 18 |
| ELVIS (USA WAIST COAT) | 18 |
| MAIAN SOLDIER | 18 |
| JOANNA STEWARDESS | 20 |
| AIR FORCE 1 PILOT | 20 |
| STEWARD | 20 |
| STEWARDESS | 20 |
| HEAD STEWARDESS | 20 |
| JOANNA ARCTIC | 21 |
| ALASKAN GUARD | 21 |
| JOANNA PARTY FROCK | 22 |
| JOANNA PARTY FROCK (RIPPED) | 22 |
| CARRINGTON EVENING WEAR | 22 |
| THE PRESIDENT | 22 |
| PRESIDENT SECURITY GUARD | 22 |
| NSA BODYGUARD | 23 |
| PRESIDENTS CLONE | 23 |
| JOANNA WETSUIT | 28 |
| JOANNA AQUALUNG | 28 |
| PELAGIC 2 GUARD | 28 |
| LEVEL | NO. OF CHALLENGES COMPLETED |
| COMPLEX | 1 |
| WAREHOUSE | 3 |
| RAVINE | 5 |
| TEMPLE | 6 |
| G5 | 9 |
| GRID | 11 |
| FELICITY | 12 |
| VILLA | 14 |
| SEWERS | 16 |
| CAR PARK | 17 |
| BASE | 18 |
| FORTRESS | 20 |
| RUINS | 22 |
| WEAPONS | NO. OF CHALLENGES COMPLETED |
| FARSIGHT XR 20 | 1 |
| GRENADE | 1 |
| SHOTGUN | 2 |
| FALCON 2 (SILENCER) | 3 |
| SUPERDRAGON | 4 |
| LAPTOP GUN | 5 |
| REMOTE MINE | 6 |
| TRANQUILIZER | 7 |
| FALCON 2 (SCOPE) | 8 |
| REAPER | 9 |
| CLOAKING DEVICE | 10 |
| DEVASTATOR | 11 |
| PROXIMITY MINE | 12 |
| SLAYER | 13 |
| PHOENIX | 14 |
| COMBAT BOOST | 15 |
| MAULER | 16 |
| CALLISTO NTG | 17 |
| CROSSBOW | 18 |
| RCP 120 | 19 |
| DY35 LX | 20 |
| N-BOMB | 21 |
| LASER | 22 |
| X RAY SCANNER | 23 |
