Avid puzzling stackexchange lurker Mr. Mnemonic (first name NOT Johnny, I promise) is having trouble remembering his login credentials. Knowing that he can be incredibly forgetful, he created a password clue device for himself that allows him to regenerate his forgotten password simply by looking at a series of characters/pictures and running them through an algorithm known only to him. However, he did not anticipate being quite so forgetful as to not remember his device! Luckily, he does have his notes from solving this the last time he forgot how to do it, which should help him figure out how he generated his passwords so he can login and post an answer to this puzzle.

Unfortunately, he did not leave a note about why his clues were so needlessly cryptic, so he'll just have to deal with that.


[house].................. I should get a boat
[star] .............................alas, no pizza
[operation]..............order matters here
[color wheel] ...............frost me once...
[prince] ..............................a true artist
[goodnight moon]..........good Morning?
[puppy]......family friend, order matters
[rose]...........................don't look down
[flat]...............greatest common factor?
[123...]...........shift these around and the password doesn't change?

Previously valid passwords:


So, given the information above, and the clue below, what is Mr. Mnemonic's current password?

enter image description here

  • 4
    $\begingroup$ Couldn't help myself :P $\endgroup$ Jun 6, 2017 at 16:05
  • $\begingroup$ Ha! Did you actually set the correct password? $\endgroup$
    – Forklift
    Jun 6, 2017 at 16:07
  • $\begingroup$ I'd have to work it out first, still haven't done that :P $\endgroup$ Jun 6, 2017 at 16:09
  • $\begingroup$ Good to get the important bits out of the way first. $\endgroup$
    – Forklift
    Jun 6, 2017 at 16:10

4 Answers 4


Putting it all together

Tumbler41's answer figured out the majority of this (make sure to upvote that one). Comments from kayzeroshort and M Oehm filled in some more.

Each image corresponds to a series of letters, or mnemonic, and the position of the image in the password indicates which of those letters to use. Here are the mnemonics for each symbol:

HOUSE house

Mnemonic: HOMES
Stands for: Huron, Ontario, Michigan, Erie, Superior
Meaning: The five Great Lakes on the Canada/U.S. border.
Clue: "I should get a boat" hints that this is referring to lakes.

STAR star

Mnemonic: MVEMJSUN
Stands for: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune
Meaning: The order of the planets in our solar system, starting from the sun.
Clue: "Alas, no pizza" refers to an earlier version of this mnemonic, which used "My very educated mother just served us nine pizzas" to include Pluto as well. Since Pluto was demoted to planetoid, the "pizza" is no longer there.

OPERATION operation

Mnemonic: PEMDAS
Stands for: Parentheses, Exponents, Multiplication, Division, Addition, Subtraction
Meaning: This is the order of operations for mathematics. It tells you what part of an equation to evaluate first (from left to right).
Clue: "Order matters here" refers to the order of operations.

COLOR WHEEL color wheel

Mnemonic: ROYGBIV
Stands for: Red, Orange, Yellow, Green, Blue, Indigo, Violet
Meaning: These are the colours of the visible light spectrum, from longest to shortest wavelength. Clue: "Frost me once..." -- The response would be "Frost me twice", which is an oblique clue to Bifröst, a rainbow bridge in Norse mythology.

PRINCE prince

Mnemonic: N/A
Stands for: numbers/symbols, because it is itself a symbol
Meaning: This is the symbol that was used by the artist Prince to refer to himself for a while, instead of using a name.
Clue: "A true artist" points people to the fact that this is a symbol for an artist, in case they had not made that connection.

GOODNIGHT MOON goodnight moon

Mnemonic: GAMEN
Stands for: Good Afternoon/Morning/Evening/Night
Meaning: This is commonly used in The Sphinx's Lair as a greeting, because there are people there from so many different time zones.
Clue: "Good Morning?" gives the clue that this may be referring to different times of day.

PUPPY puppy

Mnemonic: KPCOFGS
Stands for: Kingdom, Phylum, Class, Order, Family, Genus, Species
Meaning: This is the taxonomic order, in which all living organisms are classified, from the most general (Kingdom) to the most specific (Species).
Clue: "Family friend" is a clue to the different groupings, which include Family. "Order matters" indicates that this is the taxonomic order.

ROSE rose

Mnemonic: NESW
Stands for: North, East, South, West
Meaning: These are the directions on a compass rose, indicating the four cardinal directions.
Clue: "Don't look down" indicates that you should be looking in other directions.

FLAT flat

Mnemonic: BEADGCF
Stands for: B, E, A, D, G, C, F
Meaning: This is the order in which flats appear in music. A piece with a single flat note will have B$\flat$, while a piece with two flats will have B$\flat$ and E$\flat$, etc.
Clue: "Greatest common factor" is often abbreviated GCF, which are the last three notes in the above mnemonic.

NUMBERS $123456789$

These are different from the others. As the clue indicates, moving them around doesn't matter. They are simply modifiers for the other components of the password. A digit indicates that the character in that position of the password should be uppercase.

So a password containing the digits $3$ and $5$ would have the 3rd and 5th characters in uppercase. (An "uppercase" digit is assumed to be the associated symbol on the keyboard.)

The final answer

Using this information, we can easily solve the final password:

It will be:

  1. house h (the first characters of HOMES)
  2. operation e (the second character of PEMDAS)
  3. color wheel y (the third character of ROYGBIV)
  4. prince 4 (because the PRINCE symbol is in the 4th position)
  5. goodnight moon n (the fifth character of GAMEN
  6. puppy g (the sixth character of KPCOFGS)
  7. prince 7 (because the PRINCE symbol is in the 7th position)
  8. prince 8 (because the PRINCE symbol is in the 8th position)
  9. prince 9 (because the PRINCE symbol is in the 9th position)

But because we have the digits $148$ included as well, we "uppercase" the 1st, 4th, and 8th characters, to give us the final solution of:


  • $\begingroup$ Well, obviously this is perfect. I was hoping someone would go from Frost me once to frost me twice and jog this memory: en.wikipedia.org/wiki/Bifr%C3%B6st but that appeared to be a bridge too far (ha). $\endgroup$
    – Forklift
    Jun 7, 2017 at 15:55
  • $\begingroup$ @Forklift I've added that info. A bit too much of a leap for me, I'm afraid. $\endgroup$ Jun 7, 2017 at 15:58
  • 1
    $\begingroup$ Yeah, sorry. It was hard to find a gentle hint with that one, so I tried to balance the harder text clue with an easier picture and more of the letters in the solved passwords. My goal was for it to be solved without giving a next day hint, but not within 5 minutes either, so I feel pretty good about the result :) $\endgroup$
    – Forklift
    Jun 7, 2017 at 16:00
  • 1
    $\begingroup$ @Forklift I think it was a great puzzle. Definitely not easy, but not outside the realm of possibility. The clues (mostly) were great for confirming that I had the correct mnemonic. $\endgroup$ Jun 7, 2017 at 16:01

Putting together knowledge from the previous answers:

  1. Color wheel stands for roygbiv. Where it is in the password denotes what letter to use.

  2. Prince symbol is a number

  3. Numbers tell you which characters to capitalize.

I propose that each symbol has a corresponding word, (like roygbiv) and where it is in the password determines which character of that word to use. The words will have something to do with the symbol.

Knowing this we can piece together some of the letters of the corresponding words from the previous valid passwords. So for the house we get:

h?m?s - Which is probably homes

So looking at the others we get:

  • operation: ?em?a -> pemdas [order of operations] (kayzeroshort)

  • rose: ne?w -> nesw [compass rose has these letters] (kayzeroshort)

  • star: ???mjsun -> mvemjsun [order of planets] (kayzeroshort)

  • moon: gam -> gamen [PE meta greeting] (M Oehm)

  • puppy: ??co?g -> kpcofgs [taxonomic ranks] (kayzeroshort)

  • flat: ??adg -> beadcfg [order of flats on a piano] (kayzeroshort)

Using this information we can find the final password:


Thanks @kayzeroshort and @M Oehm for figuring out the remaining words.

  • 4
    $\begingroup$ Nice! Could be: rose -> compass rose (NESW); star -> order of planets (MVEMJSUN); flat -> order of flats on a musical score (BEADGCF) $\endgroup$ Jun 6, 2017 at 22:49
  • 3
    $\begingroup$ operation -> order of operations (PEMDAS for me, but maybe BPMDAS here?); puppy -> taxonomic ranks (KPCOFGS) $\endgroup$ Jun 6, 2017 at 22:55
  • 2
    $\begingroup$ I guess that "goodnight moon" is Gamen, the time-zone agnostic greeting from chat. (Good Afternoon, Morning, Evening or Night.) That would mean that the fifth character is an n. $\endgroup$
    – M Oehm
    Jun 7, 2017 at 8:50

Partial Answer

The clue for the digits states that you can shift them around and the password doesn't change.

I noticed that if you ignore the digits (1, 2, 3, ...), the number of images matches the number of characters in each password.

This makes me believe that each image corresponds to one digit of the password, and the numbers are simply modifiers that affect some of the images.

After "removing" the digits, I noticed that all the Prince symbols (prince symbol) correspond either to symbols or numbers in the decoded password. After a little more examination, I noticed that their positions (if you disregard digits) match their values in the password.


(where the ! corresponds to 1 on the keyboard)

My suspicion is that the number is converted to the corresponding symbol if that number is included as a digit in the image version of the password. For example, in the third password, the Prince symbol is in position 1. There is also a "1" in the images. So it becomes Shift+1 on the keyboard, or !.

I'm not sure how the clue fits ("a true artist"), or what any of the other images represent, but hopefully this can twig something for someone else.

If this is correct, the final password will be:

_ _ _ $ _ _ 7 * 9

  • $\begingroup$ You are wrong about none of this. And I couldn't be more pleased by your username. The artist clue was for people (certainly not you) that might not immediately recognize that as the Prince symbol. $\endgroup$
    – Forklift
    Jun 6, 2017 at 20:49
  • $\begingroup$ @Forklift Funnily enough, I picked my username before I'd ever heard of Purple Rain. $\endgroup$ Jun 6, 2017 at 21:00
  • $\begingroup$ I don't even know how that is possible, but well done! $\endgroup$
    – Forklift
    Jun 6, 2017 at 21:17
  • 1
    $\begingroup$ Can I add to this that the numbers don't just tell when numbers turn into symbols, but when ANY character is capitalized. For instance the first password has a 1, 2, and 7, and the first, second, and seventh letters are capitalized. $\endgroup$
    – Tumbler41
    Jun 6, 2017 at 21:46

Partial answer

The color wheels seem to correspond to the index in roygbiv order. So, for the third password, the first and sixth characters are r and i respectively.

This means the third character of the final password will be y.

  • $\begingroup$ You've also got the perfect username for your thoughts :) $\endgroup$
    – Forklift
    Jun 6, 2017 at 21:10
  • 2
    $\begingroup$ @Forklift I saw this puzzle, and I knew I had to at least contribute something. $\endgroup$
    – user27014
    Jun 6, 2017 at 21:11

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