# How were the Japanese planning to corrupt the youth of The West?

1980 - Location: Classified

"Commander, we've received a message from a deep cover asset in Japan".

"Well decode it then, what does it say?"

"Well, erm. This asset is a little eccentric boss. He doesn't trust ciphers, never uses them. But he's sent us this. Apparently if we work it out the message will show us a picture of a new threat set to conquer the world!"

You are handed a sheet of paper, each side contains a grid of letters.

|JFILLUQTWOVD|
|EMPTYSEIGHTO|
|YMMZIIXWAKLW|
|YAHYENVTORCN|
|THIRDPLUSTWO|


|PEAACR_H_J_#|
|LD__ITNK__ER|
|TCTRS##MWLM_|
|_CTULHAM_RNP|
|#_RNKIKUMF#E|
|FBSYJ__KS#LQ|
|LBUJK_#H_IBE|
|H_SKL#OLASRN|
|ABDLN#KHT_#R|
|ABIE#APKNSTG|
|_BLNOEIMSIS#|
|LCPG_LOMUXV_|
|MC#TNOEKNTWE|
|#D#HRFEHOW#R|
|WE#HFAU_NXI#|
|V_ISTCV_OYEN|


• I've been working on this for a few evenings now, got it finished before work this morning but had to wait until lunch time to write up the story and post it. Enjoy! If you have a partial solution then feel free to post it and I can confirm you're on the right lines. – Tim B Dec 15 '16 at 12:53
• We need a puzzle for this? The answer is anime, obviously! ;-) – R.. GitHub STOP HELPING ICE Dec 15 '16 at 21:56
• 1980, Japan... must be Pac-Man! ;-) – pacoverflow Dec 16 '16 at 5:27
• Beautiful puzzle :) I must admit that, at least on this site of the SE network, I generally just casually read posts and move on... This puzzle is the first to really peak my interest in a while. I intend to follow it! – Brevan Ellefsen Dec 16 '16 at 10:01
• @BrevanEllefsen Thanks, glad you like it :). The idea's been brewing for a while of embedding lots of different information in the same grid. It was pretty tricky to put together but I'm pleased with how well it's working out so far (even if I am kicking myself for having the triangles clue 1 character too short!). I originally wanted to put it all in one grid rather than having two but I decided the complexity level was already very high and the risk I'd make a mistake was growing. – Tim B Dec 16 '16 at 10:27

Varoius agents have already deduced that ...

... the message can be found by following instructions that are encoded in the grids. These instructions lead to further instructions step by step and ultimately to a "picture of a new threat", as stated in the OP's briefing.

Step 1

Techidiot and stack reader found that the upper grid contains several English words:

Across: FILL TWO EMPTY EIGHT READ EVERY THIRD PLUS TWO
Down: USING DOWN

Step 2

Read every third: Eric found out that reading every third letter from the lower grid yields:

AR_#_T_RT#W_TH_PRIMES_SQU__ES#AND#TRIANGLES#PLU_#ONE#FOR#AN#ICON

The hash marks # are spaces and the underscores _ are unknown characters, so this could mean: Start with primes, squares, and triangles plus one for an icon. (Anaylsts have confirmed that the first word isn't important.)

Step3

Start with primes ...: Reading all the letters whose indices are primes (2, 3, 5, 7, 11, ..., 181, 191) yields:

EAC__LINES#_LANK#F_LL#BLANK#A#IS_ONE#E#FIVE

or Each line's blank. Fill blank. A is one, E is five.

Step 4

... squares, ...: Similarly, reading the letters whose indices are the square numbers n² (1, 4, 9, ..., 144, 169) yields:

PA__T_#Y_L__W

which probably means Paints yellow.

Step 5

... and triangles plus one: Finally, read all letters whose indices are triangular numbers plus one, i.e. ½·n·(n + 1) + 1, which yields:

EA____S_RU_#L___TH

This could mean: each as run length. The last three steps were decoded by Daphne B.

Step 6

The following snippets of instructions haven't been used yet:

PLUS TWO FILL EMPTY EIGHT USING DOWN
For an icon.
Paints yellow.
Each line's blank.
Fill blank.
A is one, E is five.
Each as run length.

They could be rearranged into: For an icon, paints yellow each line's blank. Fill blank using two plus eight down, each as run length. A is one, E is five. Fill empty.

This seems to indicate that we should draw an icon by converting the letters in the eighth column to numbers via A1 ... Z16 and using these numbers as run lengths, i.e. adjoining units which should be painted yellow.

Now the letters in the second and eighth columns where not both are blanks gives this symmetric layout:

EH DK CM CM BK BH BK BM CM CK DH

Converting these to numbers and treating them as run lengths of leading spaces and of pixels to paint yellow gives:

start → 5, 4, 3, 3, 2, 2, 2, 2, 3, 3, 4
length → 8, 11, 13, 13, 11, 8, 11, 13, 13, 11, 8

With this information, we can print bars of yellow with the given length and starting in the given columns.

Picture of threat to humanity (SFW)

     ########    ###########   #############   #############  ###########  ########  ###########  #############   #############   ###########    ########

CHOMP! CHOMP! CHOMP!

Pac-Man was first released (or should I say unleashed?) in 1980. And it is yellow. And user pacoverflow has known the answer all along: He commented his guess while the puzzle was in early stages of decoding.

• Excellent work Commander! The analysts are aghast at the scale of the threat you have uncovered! – Tim B Dec 17 '16 at 19:22
• @M Oehm- Awesome work. To be very frank, I would have given up before reaching here. +1 for the findings. – Techidiot Dec 17 '16 at 20:02
• @Techidiot You were really close actually, you were at the final step, just needed to combine all the clues. For anyone interested the word that doesn't matter was "art", it was mostly filler though. There were two clues people missed (reading down in the main grid unencoded there were "run length" and "f is six" which were there just to help people un-mangle the sentences with the blanks in and confirm the encoding of the run length. You all didn't need them in the end but it was a bit of a safety net :) – Tim B Dec 17 '16 at 20:18
• Apart from that I think you got everything, as illustrated by the...well... illustration... above :) – Tim B Dec 17 '16 at 20:19
• @Tim B- Fab puzzle. Can't imagine all the efforts required to put it all in. – Techidiot Dec 17 '16 at 20:30

Partial findings -

First Block is

|JFILLUQTWOVD|
|EMPTYSEIGHTO|
|YMMZIIXWAKLW|
|YAHYENVTORCN|
|THIRDPLUSTWO|


Gives these words -

FILL USING TWO EMPTY EIGHT DOWN READ TO EVERY THIRD PLUS TWO DOWN ROW which sounds like a method to be applied for decoding next page. Need to check if I missed anything else.

As figured out by Daphne, we get ->

each#lines#blank#fill#blank#a#is#one#e#five. Hence, replacing the alphabets with numbers we get this . So need to check if that is solvable by any chance.

Also, after a little correction in the previous answer we get ->

E A - - - - S - R U - #L - - - TH after considering the triangles+1 pattern. Also, OP confirmed in the comments that triangles end at 18. So, there is no "E" at the end. Which might be something like EACH#AS#RUN#LENGTH Thanks to M Oehm.

So, the second grid looks like - >

P E   A   A   C   R   _   H   _   J   _   # -> 6_1_1_#
L D   _   _   I   T   N   K   _   _   E   R -> 2__4__2
T C   T   R   S   #   #   M   W   L   M   _ -> 5##4_
_ C   T   U   L   H   A   M   _   R   N   P -> _7_3
# _   R   N   K   I   K   U   M   F   #   E -> #_8#E
F B   S   Y   J   _   _   K   S   #   L   Q -> 5__2#2
L B   U   J   K   _   #   H   _   I   B   E -> 5_#1_3
H _   S   K   L   #   O   L   A   S   R   N -> 1_3#6
A B   D   L   N   #   K   H   T   _   #   R -> 5#3_#R
A B   I   E   #   A   P   K   N   S   T   G -> 4#7
_ B   L   N   O   E   I   M   S   I   S   # -> _10#
L C   P   G   _   L   O   M   U   X   V   _ -> 4_6_
M C   #   T   N   O   E   K   N   T   W   E -> 2#9
# D   #   H   R   F   E   H   O   W   #   R -> #1#7#1
W E   #   H   F   A   U   _   N   X   I   # -> 2#4_3#
V _   I   S   T   C   V   _   O   Y   E   N -> 1_5_4


or

Treating _ = 0 and # = 1

P E   A   A   C   R   _   H   _   J   _   # -> 0001
L D   _   _   I   T   N   K   _   _   E   R -> 0000
T C   T   R   S   #   #   M   W   L   M   _ -> 110
_ C   T   U   L   H   A   M   _   R   N   P -> 00
# _   R   N   K   I   K   U   M   F   #   E -> 101
F B   S   Y   J   _   _   K   S   #   L   Q -> 001
L B   U   J   K   _   #   H   _   I   B   E -> 010
H _   S   K   L   #   O   L   A   S   R   N -> 01
A B   D   L   N   #   K   H   T   _   #   R -> 101
A B   I   E   #   A   P   K   N   S   T   G -> 1
_ B   L   N   O   E   I   M   S   I   S   # -> 01
L C   P   G   _   L   O   M   U   X   V   _ -> 00
M C   #   T   N   O   E   K   N   T   W   E -> 1
# D   #   H   R   F   E   H   O   W   #   R -> 111
W E   #   H   F   A   U   _   N   X   I   # -> 101
V _   I   S   T   C   V   _   O   Y   E   N -> 00


Though...

May be one of the above is the right method. Or may be both are incorrect.

• The analysts have looked at your early findings and believe you are on the right track. It's unlikely a word would be wrapped around a corner like that though without a strong indicator to do so and they are not sure if To is significant or simply a random collection of letters. The rest does indeed seem relevant though they are not sure about how you are arranging them and what connection they might have to the second grid. – Tim B Dec 15 '16 at 15:51
• I believe the shrub length is called Bonsai size in Japan. :) But seriously, the spaces are encoded too, so this seems more like "[treat] each as run length" or some such, which could hint at counting letters between the blanks. – M Oehm Dec 16 '16 at 10:32
• @MOehm - EACH AS RUN LENGTH doesn't fit I guess. I tried other options but not able to figure out. Do you see anything with the numbers? Not sure if solving it is possible – Techidiot Dec 16 '16 at 10:34
• I think, Bonsai is the way to go ahead... – Techidiot Dec 16 '16 at 10:35
• The analysts confirm that "EACH#AS#RUN#LENGTH" fits the established patterns while EACHOFSHRUB#LENGTH would mean only one space was coded, which seems inconsistent. – Tim B Dec 16 '16 at 10:38

Another partial answer here... for now!

Going based on @Techidiot's answer, I was able to discern that you need to:

Fill the second message with... something (maybe based on 2 and 8), and then read every third character plus two.

Without doing any "improvement" of the second message, that gives you this:

AR_#_T_RT#W_TH_PRIMES_SQU__ES#AND#TRIANGLES#PLU_#ONE#FOR#AN#ICON

Which I was able to partially translate to:

AR_ START WITH PRIMES SQUARES AND TRIANGLES PLUS ONE FOR AN ICON

(I'm unable to discern the first word – there's a few possibilities.)

Given all that...

... it's likely that the hint refers to indexing using prime numbers, square numbers, and triangular numbers, possibly with one or more of those incremented by one (2, 5, 10 rather than 1, 4, 9). However, I haven't been able to make any kind of recognizable icon in this fashion.

Taking a decent break from this, hopefully someone can come up with something in the meantime!

Based on other answers people gave, I was able to fill in some of the blanks from the second message. However, I noticed that some of them conflict – I filled in the sentence I solved with red, and the others with blue.

I don't know if it helps at all, especially with those conflicts, but I figured it was worth sharing.

• The analysts are excited by your translation which they believe to be an important step forwards. They believe the first word may not be very significant. – Tim B Dec 15 '16 at 18:44

The primes -- take each letter that corresponds to a prime number (the 2nd, 3rd, 5th, etc)

without filling any blanks, translates to

eac__lines#_lank#f_ll#blank#a#is_one#e#five
Maybe:
each#lines#blank#fill#blank#a#is#one#e#five
which looks like some kind of numeric code? A = 1, E = 5?
Which looks an awful lot like each letter of the alphabet = the corresponding number? A - Z = 1 through 26?

squares

which look like

pa__t_#y_l__w
Fairly certain the second word has to be "yellow" but the first eludes me. "paints"? I don't know how this could relate to the puzzle.

Finally the

triangles (or triangles plus one, which I think is the right interpretation)
I decided not to include zero, since the squares couldn't include it
The result is:
ea____s_rm_#l___the
which frankly makes no sense to me at all, so hopefully I'm wrong.

• The analysts are very impressed with your results, convinced they bring us much nearer to a solution. On the triangular numbers they agree this clue is too mangled to easily decipher. Perhaps there are other clues yet to be found? (They also checked the indexing and think it should be ru_ not rm_ - they also received a quick note from the asset saying "humblest apologies for misleading error, triangles end at 18, there is no E at end" which seems relevant) – Tim B Dec 16 '16 at 7:48