Two years ago, I blogged about a beautiful encrypted postcard sent by a man named Fritz to his lover Leni. A blog reader has now made aware of a similar card from the same sender.

On Reddit I found two messages allegedly left behind by people who committed suicide.

Gerry Haynaly has deciphered the encrypted diary I recently introduced. Here’s how he did it.

Blog readers Richard Bean, Frode Weierud and George Lasry have broken most of the ciphertexts from the Biafran War I recently introduced.

Last week, I introduced a 750-letter ciphertext created with a bigram substitution. Jarl Van Eycke and Louie Helm have now solved this challenge. As far as I know, this is the shortest bigram cipher challenge ever broken.

According to a TV documentary, a German WW2 soldier created encrypted notes describing the location of a hidden tunnel system in Czechia while in captivity. There are rumours about a treasure hidden in this facility.

A few weeks ago, I introduced a 1000-letter ciphertext created with a bigram substitution. Jarl Van Eycke and Louie Helm have now solved this challenge and set a new world record.

Magnus Ekhall from Sweden has solved my Playfair challenge from April 2019. With only 30 letters, this ciphertext is the shortest of its kind ever broken.

Richard Bean, who recently broke two well-known cryptograms, has received lots of media coverage in Australia. Especially, a few radio interviews he gave are worth listening.

Earlier this week, I blogged about two encpostcards sent to a Bavarian princess. My blog readers solved all the mysteries about these documents.