So on October 6th 1o57 (who creates the DEF CON badge challenge) gave a fantastic talk at the hackaday 10th anniversary which you should totally watch:

(go ahead, I’ll wait)

You might have noticed some random text in the slides, but you might not have. Anyway here are the slides

And here is a copy of all the letters on each of the slides


on one line:


Hrmmm, well the first thing you might try is a Caesar cipher. In the video you’ll notice that 1o57 repeatedly mentions that it’s Hackaday’s TENTH anniversary, so we should try decrypting the above string with a key of 10. (here’s a tool do to that)


(side note: I cheated on this step by using an automated caesar cipher breaker)

Hrmmm that still looks like nonsense, but it does start with the word ten, so we’re probably close...

Wait a second! The string is backwards! It’s not ten it’s net!


or cleaned up

Send codeword to

Ok, well now we know where to send the codewords. The only unsolved part of the puzzle is this last slide

WTF are those things?! Now fans of Sherlock Holmes may recognize these, but at the time I did not, so I went to my best friend Google to try and figure it out. I tried lots of search terms like “stickman code" (and variants on that) and “semaphore" (since I thought maybe the positions on the flags was significant), until I came across this page:

which features a code called the Dancing Men!

This code comes from a Sherlock Holmes novel called The Adventure of the Dancing Men

And we can use the above image to decrypt the band, which decrypts to:

codeword psychobilly ciphers

Thanks for the fun puzzle 1o57!