Good Ol' Fashion Crypto

[Stefunny]

What? Are they worried about floods?

[Packbat]

No, the Flood only turn up in single-player Halo.

[Stefunny]

Or in Genesis.

[Stefunny]

Hmmm, Packbat do you play Xbox games?

[Packbat]

Occasionally, but more Left 4 Dead than Halo - and more Test Drive Unlimited and Forza Motorsport 2/3 than Left 4 Dead.

[Stefunny]

Occasionally, but more Left 4 Dead than Halo - and more Test Drive Unlimited and Forza Motorsport 2/3 than Left 4 Dead.

TDUL2????
You are my new best mafiascum friend. You have heard of the Unicorns right? We play halo pretty much every wednesday, we play some other games occasionally when we feel the urge.

http://mafiascum.net/forum/viewtopic.php?f=6&t=15771
also
http://mafiascum.net/wiki/index.php?tit ... n_Brethren
but ignore the part where it says I'm inactive, RC is slow.

[Mist7676]

NO PACKBAT DONT JOIN THEY ARE CRAZY!!!!! *licks eye*

[inspiratieloos]

What kind of code is it?

It's a simple substitution cipher...

honestly

Hint: I like to fight fire with fire



The real cipher is just a part from a book, so some common sequences might be names instead of common words. The scene is very funny in context, but maybe not so much if you don't understand the references.

[inspiratieloos]

BUMP
Should I start giving hints or is just no-one attempting this cipher?

[Nobody Special]

I have just discovered this thread. I absolutely adore ciphers and codes and such. Can I have a day or so before you give the answer?

[theplague42]

Same for me. Exams are over, and I have most of today to work on it. If neither me nor NS get it by Sunday, you can post the answer.

[inspiratieloos]

I'll probably post some hints before giving the full answer

[inspiratieloos]

Hint: The cipher is Playfair, the key is the (unofficial) name of the series

Mist's hint: If you didn't figure it out yet, I cheated (which is why I didn't just post it for everyone)

[theplague42]

@NB
Lol awesome sig.

Playfair?!? We already failed once at doing one... I though you said it was a simple substitution cipher

[Mist7676]

Tht was mine

[Nobody Special]

Well, no wonder I wasn't making any headway.

[inspiratieloos]

I kind of assumed Packbat would immediately come up with his frequency analysis, it should be long enough to easily solve that way.

[Nobody Special]

You know what happens when you assume, right?

[Packbat]

I kind of assumed Packbat would immediately come up with his frequency analysis, it should be long enough to easily solve that way.

Oh, right, I didn't do that one yet.

Single-letter frequencies:

Code: Select all

 A  B  C  D  E  F  G  H  I  J  K  L  M  N  O  P  Q  R  S  T  U  V  W  X  Y  Z
59 51 24 48 77 34 28 31 11  0 57 85 64 23 60 62 46 23 28 69 11 18  4 56 12 59

Digraph frequencies (first letter top/bottom, second letter side):

Code: Select all

    A  B  C  D  E  F  G  H  I  J  K  L  M  N  O  P  Q  R  S  T  U  V  W  X  Y  Z
A|  2  2  0  2  3  1  0  1  0  0  1 19  4  0  5  2  2  0  0  6  0  1  0  2  0  6 |A
B|  5  0  1  2  4  1  0  3  1  0  6  5  3  1  4  3  0  0  1  4  0  3  0  0  1  3 |B
C|  3  1  0  0  2  0  2  0  1  0  1  0  2  0  0  1  1  0  2  3  0  3  0  0  0  2 |C
D|  3  1  1  1  5  0  1  1  0  0  3  3  2  1  4  3  0  2  5  7  0  1  0  0  1  3 |D
E|  2  2  2  2  0  3  3  3  0  0  3  6 18  1  1  9  3  1  0  3  0  0  1  8  1  5 |E
F|  2  5  0  1  3  0  0  0  0  0  3  4  4  0  1  0  3  1  0  3  0  0  0  1  0  3 |F
G|  4  1  2  0  1  0  0  2  0  0  1  6  1  1  1  0  2  0  0  2  1  0  0  2  0  1 |G
H|  3  2  2  1  6  1  2  0  0  0  1  1  1  1  2  6  0  0  0  1  0  0  0  1  0  0 |H
I|  0  0  0  0  1  1  0  0  0  0  0  0  0  0  3  0  0  1  0  0  0  2  0  1  0  2 |I
J|  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0 |J
K|  2  8  0  2  4  3  2  3  6  0  0  4  0  1  5  0  4  1  2  4  0  2  3  0  0  1 |K
L|  1  5  3  1  7  1  0  0  0  0  2  0  0  3  4 17  5  4  1  8  1  1  0  5  4 12 |L
M|  4  0  0  2 10  1  1  3  1  0  4  6  4  2  2  2  0  7  0  6  2  2  0  2  0  3 |M
N|  2  1  0  0  1  0  0  1  0  0  0  2  0  0  0  6  0  0  0  1  1  1  0  1  2  4 |N
O|  9  4  0  8  1  9  1  0  0  0  6  1  6  2  1  3  3  0  5  1  0  0  0  0  0  0 |O
P|  6  1  0  9  4  2  2  3  0  0  2  6  6  3  9  1  2  1  0  3  0  0  0  1  1  0 |P
Q|  1  0  1  1  3  9  2  4  0  0  8  6  1  2  0  1  1  0  0  2  2  0  0  1  0  0 |Q
R|  0  4  0  0  4  0  1  1  0  0  0  1  0  0  1  0  0  0  3  0  0  1  0  1  2  4 |R
S|  0  0  3  4  0  0  2  0  0  0  2  2  1  0  1  0  3  0  0  4  0  0  0  3  0  3 |S
T|  2  0  2  6  8  0  0  4  1  0  7  7  7  2  5  1  4  0  0  0  0  0  0 10  0  3 |T
U|  0  2  0  1  0  1  0  0  0  0  0  1  0  1  0  0  0  2  0  0  0  0  0  3  0  0 |U
V|  2  1  0  1  0  1  2  0  0  0  5  0  1  1  0  0  0  0  0  0  1  0  0  3  0  0 |V
W|  0  0  0  0  0  0  1  0  0  0  0  0  0  0  0  0  0  0  0  2  0  0  0  0  0  1 |W
X|  3  1  4  1  2  0  2  2  0  0  0  1  1  0 10  6 11  3  1  2  1  1  0  3  0  1 |X
Y|  0  5  1  1  0  0  1  0  1  0  0  0  0  0  0  0  0  0  1  0  0  0  0  1  0  1 |Y
Z|  3  5  1  2  8  0  3  0  0  0  2  4  2  1  1  1  2  0  7  7  2  0  0  7  0  1 |Z
    A  B  C  D  E  F  G  H  I  J  K  L  M  N  O  P  Q  R  S  T  U  V  W  X  Y  Z

[Packbat]

The big numbers in the digraphs are LA (19), ME (18), and PL (17), followed by ZL (12), QX (11), and XT, OX, and EM (10). I haven't checked for parity on any of this, mind, so a fraction of these results are going to be fallacious.

ME+EM suggests a reversible digraph, obviously.

[inspiratieloos]

Code: Select all

QG HA MT LG WK QX LQ EX TD XU QL KT DO MT ZT WK DS RD EH BY LT OF TD TH LB ER DH FQ SB TE SX HD TC XU ER LA DQ KB OB VI KG IV HA XT KZ VH TN HB FO KZ AB UM TM EB NQ TD OA PN QT GE TL BU LQ LP LA AP HQ XT BL FO IT ZM QK ME PL AO IK VA HK TM OM ZA YC PL FQ BG CT LK QX FK LD LQ AP XZ KE DM SD KE ZB FO KT AT FK ME DU QT GE TL BF OP LA DY BZ MP BK PO ZC YN HM ZF PL ME DO HE TD BY PH RE KB KB XS XT BL FO HE CH ME FQ OX UN VX LG RX EH BY LT OF DY XG SG ME IK AH ND GV LA QF ZE SX RD XE MF MP EC LN IK AS AO SG LT QG HA ZE KE PL DZ PH MR RO XE MZ QV LQ PH PM AM ZD PL MD BO MP PL MT GX AM XT ME DO KB ME PL EP ON LA CK TL ZL ZA YC XT BL UM OX AB RM PL AO CO ZS ZL XT LQ MH ZL TN DH FQ CG WX SC AO QL XT AH LS TM KF OF TD AV XT EM EB YI VB YK KZ GX VI MT PL AZ EZ AO DP DO XZ PN ME KG LA DR ZE OA OM VI ZD SM OR KZ PL AO WX SC AO QL XT PL EP ZG QX EZ GX AB RU ZS ZL AH RM KB HG OX ZA TN PH PE OD TN BH QU LT OF TD AV DO ZL KD ET XT LT PH ED MO MT SD AN BH XQ FQ XI CT LQ SD KE ZB FO KO XT QL UX ME LA GV DV ME GX AB RU ZS ZL GV LQ LP LA GC ZL BA OP PH PE TE QX GQ PL PL AO GK MT OD OB OM HC LQ DM EP XZ PE FO TZ LA EM OD PN PM AM OP XL KQ OP TH DS LZ MB KO LA HT ME XZ ZE TM KF OF TD AV XT EM ER YC FQ OQ XG PH TD XZ NO PL MD HE AM FQ EM OM ER MB KO SO XT XY NC TD BK PE FL ME DP XZ RM AB RU VB ZA QK QX ZS ZL PC LA EM OK DP ME QT XZ EK CD ET XT LT SD KE ZB FO FE ZN ON DT ME GX AM PL FQ CB DP LF ZR SL FB OA FH TX EG KC GQ PL DU PH KQ FK TM AP XZ KE AZ DT HK RM IK AX LT LN LA OX FM AB RM FQ CX NM HK OD TC HM OP DP AP HQ SD FO TL ER LA CX MC EB FU ME MT ZL TQ QK OA LA CQ GZ TL MC

I put the cipher in digraphs, which should make it a bit easier to handle visually. This is also the original so any mistakes I might have made converting it to 5 letters shouldn't be in here.

Hint: The key has 6 letters, none of which are repeated.
And for the lulz: MT ZL TQ QK OA = Enterprise (this is a bit of a red herring though, but I can also see it being very helpful)

[theplague42]

Must be Star Trek....

[inspiratieloos]

I can't figure out if you're serious or not...

[theplague42]

Nada.










But was I right?!?!?

[inspiratieloos]

No... Obviously