All Difficulty Modes:
1 D2CT-CADY Game clock runs faster
2 SACT-CADY Game clock runs slower
3 8ACT-CADY Game clock runs much slower
4 AACT-CA6J Game clock frozen (no time limit)
5 AJBT-AAEY Start at stage 2 instead of stage 1
6 ANBT-AAEY Start at stage 3
7 ATBT-AAEY Start at guardian level after stage 3
8 AYBT-AAEY Start at stage 4
9 A2BT-AAEY Start at stage 5
10 A6BT-AAEY Start at stage 6 I
11 BABT-AAEY Start at guardian level after stage 6
12 BEBT-AAEY Start at stage 7
13 BJBT-AAEY Start at stage 8
14 BNBT-AAEY Start at stage 9
15 BTBT-AAEY Start at guardian level after stage 9
16 BYBT-AAEY Start at stage 10
17 B2BT-AAEY Start at stage 11
18 B6BT-AAEY Start at stage 12
19 CABT-AAEY Start at guardian level after stage 12
20 CEBT-AAEY Start at stage 13
21 CJBT-AAEY Start at stage 14
22 CNBT-AAEY Start at stage 15
23 CTBT-AAEY Start at guardian level after stage 15
24 AJNA-EA3R Infinite ammo for machine gun
25 AJMA-EA7C Infinite fuel for flame-thrower
26 AJJT-EA2J Infinite ammo for grenade launcher
27 AJKA-EA88 Infinite hand grenades
28 M42A-CAG0 Machine gun recharge pick-up reloads to
capacity
29 NC2A-CAHY Flame-thrower recharge pick-up reloads to
capacity
30 NL2T-CAAW Grenade launcher recharge pick-up reloads to
capacity
31 NW2T-CABT Hand grenade recharge pick-up reloads to
capacity
32 RG2T-C6W4 First-aid pick-up restores energy gauge to
capacity
33 AMDA-CA4J Long falls do not reduce energy
34 ADEA-CAGJ Falls into turbine fans do not reduce energy
35 AJFT-AA66 Never lose radar
36 A2EA-AA8R Infinite lives
37 5DXA-D93N Ripley jumps higher
38 YDXA-D93N Ripley jumps much higher
Hard Difficulty Mode:
39 LBRT-JAEJ Machine gun capacity is 50 instead of 99
40 GBRT-JAEL Flame-thrower capacity is 30 instead of 99
41 EBRT-JAEN Grenade launcher capacity is 20 instead of
99 E
42 GBRT-JAER Hand grenade capacity is 30 instead of 99