List out all of the highlighted letters: afiafhafgbfibfhbfgcehcegcdhbeibdibegbehbdhadg
Now, notice that each of these letters are found in the 3D grid below as indicators of a coordinate system. Now, three at a time, put them in each of the fifteen blanks below.
1 afi 1 afh 1 afg 1 bfi 1 bfh 1 bfg 1 ceh 1 ceg 1 cdh 2 bei 2 bdi 2 beg 3 beh 3 bdh 1 adg
Each of these fifteen entities are coordinates of the corresponding number clue in the 3D minesweeper board. For example, the cube with the coordinates "afi" has a clue of 1, meaning that the cube borders exactly one mine on either a face, edge, or corner.
Note that from the header (or from 3 beh), there are three mines. From 2 beg, we know that there is exactly one mine in the group (adi, aei). From 1 adg, we know that there are two mines among the group (adi, aei, cdg). Thus, we deduce that there is a mine at cdg. From 1 afg, there is one mine in (aeh, aeg). From 1 afh, there is one mine in (aei, aeh, aeg). Thus, there is no mine at aei, so there is a mine at adi. Finally, note that 1 afi, 1 afh, 1 afg clue to a single mine in the same set of three squares, and since aeh is the only common square between them, aeh has a mine.
The arrow below the minesweeper board signifies to list the letters in the mines from left to right, getting ADIAEHCDG.
The equation translates to "psi + fern - n = psifer," which sounds like cipher. The image below is a running key cipher. The mention of dots and dashes hints for you to use Morse code on the key, getting a key of WRHMMPUQA. Decrypt the letters from the mines with the key to get the answer of EMBOSSING.