To enter a code, you must first access the password screen. (Choose “Load Game” at the main menu then press B.) Thereafter, activating a cheat requires entry of its corresponding password. 

Cheat Password
Additional colors S3TC 00LC 0L0R S???
Unlimited Ammo* S3T1 NF1N 1T3S H0TS
Higher Jumps* S3T1 NF1N 1T3S H0TS
Reduce Gravity* S3TL 0WGR V1TY ????

* Multi-player mode only. 
Level 0: Twists 
To play Twists, deathmatch where players do battle with rocket launchers, you must first access the password screen. (Choose “Load Game” at the main menu then press B.) Thereafter, activating a cheat requires entry of its corresponding password.

Level Password
Twists (Easy)* FBBC VBBB FBBC VBB7
Twists (Medium)* FLBC ZBBB FLBC ZBB9
Twists (Hard)* FVBS LBBB 7VBC 3BB5

* The last two digits are adjustable. The second-to-last digit to changes health. (B=2, C=34, D=66, E= not used, F=99, G=3, H=37, I= not used, J=68, and K=100 health points) The last digit adjusts time. (3=1:42, 4=1:43, 5=1:14, 6=1:43, 7=1:46, 8=not used, 9=1:42.) 

Passwords (Easy)  -  To enter a code, you must first access the password screen. (Choose “Load Game” at the main menu then press B.) Thereafter, activating a cheat requires entry of its corresponding password.

Level Password

0: Twists* FBBC VBBB FBBC VBF7
1: Central Complex ---- ---- ---- ----
2: Intelligence Center 6JBN SHFB 07BR X3J1
3: Communications Center 1KLG VL2H LNBF F4LQ
4: Orbital Defense 2KQD 2MSD Z9VM 4XYL
5: Docking Station VK7N Z?LY ?4V5 LJ4W
6: Strogg Frieghter VK3J HSW5 9GZN LQW9
7: Cargo Bay TK3T RN5N Q06W JV05
8: Zaxite Mines S?WM H1G9 B46C WBOD
9: Storage Facility R8WB 8X7J VGQ0 SJWR
10: Organic Storage Q?WB BLW8 RP6Y XLSN
11: Processing Center P6P5 KYWX HB8R DJZH
12: Geothermal Station N520 KJFW Y681 VLMD
13: Detention Center M525 TZ35 HXW0 BXZ8
14: Research Lab L56X 41DX ZKR8 VJV8
15: Bio-Waste Treatment K58V 01HJ V5K9 C3VK
16: Access Conduits J584 W6NR D05B VDQ?
17: Descent to Core H522 98MJ SM1C B82C
18: Command Core G52W 300Z 561C W4HK
19: Final F569 G2D6 HT6X SG5Y
End F60? VQCH ?BHF DQQL
* Deathmatch 

Passwords (Hard)  -  To enter a code, you must first access the password screen. (Choose “Load Game” at the main menu then press B.) Thereafter, activating a cheat requires entry of its corresponding password .

Level Password  -  0: Twists* FVBS LBBB 7VBC 3BF5
* Deathmatch 

Passwords (Normal)  -  To enter a code, you must first access the password screen. (Choose “Load Game” at the main menu then press B.) Thereafter, activating a cheat requires entry of its corresponding password.

Level Password

0: Twists* FLBC ZBBB FLBC ZBF9
1: Central Complex ---- ---- ---- ----
2: Intelligence Center PGBR VK?B 65BH Y3HD
3: Communications Center 1KLS DN5H 7NBF DWRQ
4: Orbital Defense 2KLR SDRY ?VV4 YQ8X
5: Docking Station VK3T 7LFC 94B7 D3R3
6: Strogg Frieghter WK3H QNBW NLV5 XGL3
7: Cargo Bay TK7P 6LLP KWGY XD4V
8: Zaxite Mines ST0N QPX4 2WGY JXTS
9: Storage Facility R??P 7NY4 2WGX 99TX
10: Organic Storage Q??K BBBV NBQ1 7GCV
11: Processing Center P64? ZM5B ?BM0 5YH6
12: Geothermal Station N664 SQ63 XB?K B7LF
13: Detention Center M682 M7QT 1215 8098
14: Research Lab L669 H8MD G8XB JNYV
15: Bio-Waste Treatment K681 X8CL H01K 1PF5
16: Access Conduits J6?0 BT5M NRZ2 QXLL
17: Descent to Core H6?0 XXFW PHV1 77P4
18: Command Core G6?9 GYMK RWNK SMSL
19: Final F6Y3 WXQK CHD0 8K4D
End F60? VQCH ?BHF DQQL
* Deathmatch 

Toasted Marines  -  On the detention center level, you'll notice captured marines all throughout the level. In one room, there are a three marines in a cage above a lava pit. Once you are on the top level of this room, press the green button in the corner. The cage full of marines will slowly fall into the lava pit. Press the button again, and the cage will come back up - now containing armor!