In computer software and media, an Easter egg is an intentional inside joke, hidden message or image, or secret feature of a work.

https://en.wikipedia.org/wiki/Easter_egg_(media)

There is an interesting way of finding the infamous Halloween Card symbol in the z340 cipher. Maybe it was intentional (or not) on the part of the Halloween card author (the author being the zodiac, or not; who knows).

So, just as a reminder, here are the 2 versions of the HC symbol, found in the card and its envelope:

You’ll notice that, in both cases, a "Z" is written right next to the symbol.

Let’s hypothesize that the symbol is actually a "7" and an "F" merged together as follows:

Now, let’s split the z340 in quadrants and flip and/or rotate these quadrants to look like the following:

You’ll notice I highlighted 4 "by" symbol groups; they happen to be arranged like in the Halloween card.

Next, choose the following 7 "F" symbols:

If you trace an imaginary line between these symbols, you get

This is starting to look like the Halloween card symbol. I overlayed it to compare:

Now, did you notice something else? The z340 contain a total of 4 "Z" symbols. They happen to line up exactly with the 4 dots in the symbol:

What are the odds?!? Happy Easter!

pi_