THE RECIPE HAS BEEN FOUND

Step 1

Step 2

Step 3

Step 4

What we know so far

There are 12 locations where runes can spawn, shown below :

Bringing a blue torch to those spot will reveal symbols (The number of and symbols are random per player), some of which will be colored

Each Symbol corresponds to a number, delimited by the number of bump on that seal in the portal in front of the spider god's door, as shown below :

With this in mind, each colored rune is actually an X/Y coordinate and a color :

The current theory is that by plotting these symbols, we can get an image that will help us unlock the "Cheat Code" item

Kill it With Fire 2 Mosaic

This event has now been solved, below are the community's final mosaic, along with the full solution

Community Solution


Full Solution