Now - a foreword; this is all going on the assumption that the level codes at GameFAQs (https://gamefaqs.gamespot.com/saturn/574032-3d-lemmings/cheats) are accurate. I cannot find another source either confirming or disproving that assumption (though I didn't look super hard). I do notice two codes are an extra character long; these might be typos, or errors in the game.
But there's some interesting messages in the codes, for sure.
First, here's the list of codes, in actual level order (GameFAQs uses alphabetical order, which is slightly wrong here):
Spoiler
02 STARTING
03 DIFFRENT
04 PLECTRUM
05 ROBINSON
06 GREGATIM
07 FUNCTION
08 BLANDISH
09 LAMPWICK
10 MURLITION
11 SURPRISE
12 TRAPDOOR
13 FIGUERAS
14 SANDWICH
15 BATEMANS
16 PANGOLIN
17 GARGANEY
18 PECULIAR
19 ESPANOLA
20 WOBEGONE
21 TRISTART
22 SHOBNALL
23 CURLICUE
24 BILLYCAN
25 GOLDPEAK
26 GRIPPING
27 FUGITIVE
28 FEARLESS
29 SPITULUM
30 BESLAVER
31 ANABLEPS
32 QUINCUNX
33 TARLATAN
34 YANGSING
35 GUMMOSIS
36 PRODNOSE
37 NGULTRIM
38 COTTABUS
39 THANKSTO
40 BIERHAUS
41 TAXSTART
42 AFBAMIXS
43 BRADFORD
44 SHEEPAND
45 SMARMITE
46 CHEAPGAG
47 THINKYOU
48 PROBABLY
49 CANTREAD
50 NEXTONES
51 TSTDFWTO
52 HOHOOHHF
53 EMAWROAT
54 SETNTETH
55 ECRWHNSA
56 AOEAOJON
57 RDARSORG
58 EEDDEYTX
59 XSXSXXXX
60 FOOTBALL
61 MAYSTART
62 TASHKENT
63 ZULUDAWN
64 QUATRAIN
65 GRANDCRU
66 WITTMANN
67 WHATNEXT
68 UNCTIOUS
69 EVERARADS
70 ENTREATY
71 GLACKIAN
72 WHEEEEEE
73 IKEIMMEL
74 MORROCCO
75 TWOPOINT
76 FOLLICLE
77 SPROCKET
78 METARULE
79 FALLBACK
80 BEANCURD
Of particular interest are:
21, 41, 61: TRISTART TAXSTART MAYSTART - note these are the first levels of Tricky, Taxing and Mayhem respectively (hm, wonder if the unlisted code for level 01 is "FUNSTART"...)
39 and 40: THANKSTO BIERHAUS
46 to 50: CHEAPGAG THINKYOU PROBABLY CANTREAD NEXTONES
51 to 59, these need to be arranged vertically:
TSTDFWTO
HOHOOHHF
EMAWROAT
SETNTETH
ECRWHNSA
AOEAOJON
RDARSORG
EEDDEYTX
XSXSXXXXReading this top-to-bottom, left-to-right, and dropping the X's, this reads: "these are some codes that read downwards for those who enjoy that sort of thang" [sic]
Also, code 72 is WHEEEEEE. Not so much of an easter egg in and of itself, but both myself and GigaLem found this highly amusing.
I couldn't find any mention of this anywhere with a quick Google search. Is this known?
This reminds me of some of the hidden messages found in the Acorn Lemmings/ONML codes (http://www.4cheaters.de/archimedes/cheats/lemmings-oh-no-more-lemmings-2239) (see Crazy 12 to Wild 2 for example, and Wicked 1 to 12).
I think it's easy to miss because even if you are writing down the codes on paper to look up later, as a player you will usually just go look for the most recent code so you can resume playing, rather than carefully reading through a sequence of them.
As for Google, well now that you have this thread created, maybe future Googlers looking for mentions of this will be directed here. ;)
I've extracted the game data from the Saturn disc, and I found a string of text that matches up with the password list.
Spoiler
1 FUNSTART
2 STARTING
3 DIFFRENT
4 PLECTRUM
5 ROBINSON
6 GREGATIM
7 FUNCTION
8 BLANDISH
9 LAMPWICK
10 MIRLITON
11 SURPRISE
12 TRAPDOOR
13 FIGUERAS
14 SANDWICH
15 BATEMANS
16 PANGOLIN
17 GARGANEY
18 PECULIAR
19 ESPANOLA
20 WOBEGONE
21 TRISTART
22 SHOBNALL
23 CURLICUE
24 BILLYCAN
25 GOLDPEAK
26 GRIPPING
27 FUGITIVE
28 FEARLESS
29 SPITULUM
30 BESLAVER
31 ANABLEPS
32 QUINCUNX
33 TARLATAN
34 YANGSING
35 GUMMOSIS
36 PRODNOSE
37 NGULTRUM
38 COTTABUS
39 THANKSTO
40 BIERHAUS
41 TAXSTART
42 AFBAMIXS
43 BRADFORD
44 SHEEPAND
45 SMARMITE
46 CHEAPGAG
47 THINKYOU
48 PROBABLY
49 CANTREAD
50 NEXTONES
51 TSTDFWTO
52 HOHOOHHF
53 EMAWROAT
54 SETNTETH
55 ECRWHNSA
56 AOEAOJON
57 RDARSORG
58 EEDDEYTX
59 XSXSXXXX
60 FOOTBALL
61 MAYSTART
62 TASHKENT
63 ZULUDAWN
64 QUATRAIN
65 GRANDCRU
66 WITTMANN
67 WHATNEXT
68 UNCTIOUS
69 EVERARDS
70 ENTREATY
71 GLACKIAN
72 WHEEEEEE
73 IKEIMMEL
74 MORROCCO
75 TWOPOINT
76 FOLLICLE
77 SPROCKET
78 METARULE
79 FALLBACK
80 BEANCURD
81 SPACEXXX
82 EGYPTXXX
83 ARMYXXXX
84 MAZEXXXX
85 KRAUTROK
86 TOECHEEZ
87 PASSWORD
- SPACEXXX, EGYPTXXX, ARMYXXXX and MAZEXXXX play the FMVs that play when you beat the Fun, Tricky, Taxing and Mayhem difficulties respectively.
- KRAUTROK is the level select password.
- TOECHEEZ and PASSWORD are accepted as passwords, but I don't know if they do anything.
Cool. :D
So, as I mentioned in Discord - the fact that this lead us to closer examine the passwords in that version, has lead to us discovering a level select code that went unknown for nearly 24 years since the game's release - even when a level select code was known to exist on PS1. Wow. :O
The next question is whether one also exists in the PC version. Unfortunately, not much luck has been had trying to even find where it stores the passwords.
Also, I made a video of the RASPUTIN cheat in the PC version. Although the cheat has been known for a long time, I couldn't find any existing video footage of it, so I made some.
https://www.youtube.com/watch?v=0H95Zou5bXM
In the PC version, near where the password is stored in memory (as in, the one you've entered on the password screen), there are 8 bytes that change depending on the password entered. The first byte will always have the same value, if the first character is the same. Likewise, the second byte will have the same value if the second character is the same. But if the first two characters are the same, the first and second byte will be different. Here's the codes for all 27 strings of one character, including empty (from which any combination can be derived, due to the aforementioned rules):
AAAAAAAA : 1E 1F 0F 07 03 11 08 04
BBBBBBBB : 1F 1E 0E 06 02 10 09 05
CCCCCCCC : 1C 1D 0D 05 01 13 0A 06
DDDDDDDD : 1D 1C 0C 04 00 12 0B 07
EEEEEEEE : 1A 1B 0B 03 07 15 0C 00
FFFFFFFF : 1B 1A 0A 02 06 14 0D 01
GGGGGGGG : 18 19 09 01 05 17 0E 02
HHHHHHHH : 19 18 08 00 04 16 0F 03
IIIIIIII : 16 17 07 0F 0B 19 00 0C
JJJJJJJJ : 17 16 06 0E 0A 18 01 0D
KKKKKKKK : 14 15 05 0D 09 1B 02 0E
LLLLLLLL : 15 14 04 0C 08 1A 03 0F
MMMMMMMM : 12 13 03 0B 0F 1D 04 08
NNNNNNNN : 13 12 02 0A 0E 1C 05 09
OOOOOOOO : 10 11 01 09 0D 1F 06 0A
PPPPPPPP : 11 10 00 08 0C 1E 07 0B
QQQQQQQQ : 0E 0F 1F 17 13 01 18 14
RRRRRRRR : 0F 0E 1E 16 12 00 19 15
SSSSSSSS : 0C 0D 1D 15 11 03 1A 16
TTTTTTTT : 0D 0C 1C 14 10 02 1B 17
UUUUUUUU : 0A 0B 1B 13 17 05 1C 10
VVVVVVVV : 0B 0A 1A 12 16 04 1D 11
WWWWWWWW : 08 09 19 11 15 07 1E 12
XXXXXXXX : 09 08 18 10 14 06 1F 13
YYYYYYYY : 06 07 17 1F 1B 09 10 1C
ZZZZZZZZ : 07 06 16 1E 1A 08 11 1D
(empty) : 01 00 10 18 1C 0E 17 1B
EDIT: Upon further inspection, this is just using A = 0 (and blank = 31), with the final string XOR'd with 1E 1F 0F 07 03 11 08 04.
There are two more nearby bytes that vary with the password entered. One of these has a value of 0x65 for an invalid password, or 0x54 for a valid one. The other varies from (at least as far as I've seen) 00 to 08. This does not appear to be connected to the password being correct - two correct ones resulted in 0x05, while another gave 0x03. 0x05 has also occurred on an invalid password.
In a memory dump, look for the following. In my memory dumps (DOSBox 0.74 debugger build, via "memdumpbin 0:0 128000"), this starts at offset 0x011844.
XX 0B YY 45 6E 74 65 72 20 50 61 73 73 77 6F 72 64 00 WW WW WW WW WW WW WW WW 00 2E 0B ZZ ZZ ZZ ZZ ZZ ZZ ZZ ZZ
where:
XX - The byte that's 0x65 or 0x54 depending on password validity
YY - The byte that varies from 0x00 to 0x08
WW - The entered password, in uppercase plain ASCII
ZZ - The 8 bytes with the encoded password
Searches in the EXE file or dumped memory for encoded copies of the correct passwords, including via packing it into 5 bits x 8 characters = 5 bytes, has not produced any useful results; nor has memory searches for packed copies of the entered password.
EDIT: Upon further testing, YY may vary even when entering the same password multiple times - so it's quite possible it simply tracks an animation frame.
EDIT AGAIN: YY's function confirmed. It's a byte that counts down to figure out, after hitting enter, how long until the screen should begin fadeout.
Seems no one posted, so update - while we never fully cracked how the PC version stores the codes, we did figure out where it stores them. And just from this alone, we were able to confirm that the PC version doesn't have any secret codes - unless they're more of the RASPUTIN variety, where they're typed in during gameplay rather than at the password screen. It's very interesting though, that the PC version goes to all this trouble to hide the passwords (which would've been just 160 extra bytes to leave in plaintext like they are on other versions), while the other two versions store their passwords in plaintext - especially in the case of PS1, where the passwords are the same as PC (except for the addition of 5 secret ones).
We also confirmed no more unknown codes exist on the PS1 version - just the four FMV ones and "LAMPWICK", which have been known for ages.
Pooty did mention the string "assassinated" (but not any of the postview messages associated with RASPUTIN) appears in the ROM of the Saturn version. I just checked the Playstation version, and the same is true there.