There are some hidden Achievements in Muck. If you take a look at the Achievement page and scroll through it, you will find one or two hidden Achievements.
Today we are talking about how to find the hidden achievement "Oh you don't know what Karlson is?". This is obviously a reference to the game Karlson that Dani has been working on for some time.
Anyway, let's get started!

You can find Billy on any seed. The easiest way to do this is to go to the settings and under "Settings" then under "Graphics" uncheck "Show Grass" .


However, in Muck you also have the option of generating a world after a seed. In the following seed, the spawn of "Billy" is near the player at the beginning.


He is located in the direction of the hut in front of a birch tree. If you use the trick from above, you should find Billy quite easily, otherwise it will be a little more difficult ;).

The Seed i used was: 931098003









EDIT:
Due to the last update that Dani released, the seeds no longer work as they did before. Billy is still on the map, but he is in a different location. User Sayonara found out exactly where, thanks to you by the way!

This is where Billy can now be found:

Big Shoutout to Serroh who uploaded a Video to this topic and other usefull stuff about Muck. Check him out!
Watch the Video who helped me making this and support him.

Thanks also to Sayonara for correcting my mistake!
Here is his Steam profile:

Thank you all for reading!