Fortnite's Decryption Challenge Fortbyte number 13 is located at Fatal Fields. Go to the main house, go upstairs, take the second door on the right and there you go! No need to have a particular skin or to perform a special action to unlock it.
Written by Augustin "TheGreatReview" Héliot. Translated from French by Millenium.us.org.
The challenges and Fortbyte locations of the Fortnite Season 9 decryption challenge, as well as the complete list of Fortbytes, are to be found in this article.
