by Kurgan » June 7th, 2021, 9:55 am
If you have no other excuse to differentiate squares and feel outright grid lines would be jarring and unnatural, you can always use dirt patches, piles of bones or other debris, light and shadow to do the trick in a creative way, though it will take more time to implement. Great idea above about the roots, vines or other vegetation forming the "boundaries!" Water "patterns" is a great idea too.
Dropped ropes or chains might conveniently work too. Different weathering patterns, scratches, blood spills or rocks can also do the trick.
Wood - parquet flooring!
Grass - mowed/plowed in squares (saw this solution in an old "learn about chess" book from my childhood, also reminiscent of the "Space Harrier" games).
Could also be patterns of light and shadow, like from cloud cover if you really want to be subtle.
Cavern - thin lines of stalagmites, cleverly placed cobwebs, little "streams" of water? It's stone, so cracks work here too as well as veins of minerals.
Dirt - cracks, foot or animal tracks/wagon marks... critter scat, even traced lines cut into the dirt (sometimes people draw lines in the dirt too!).
Metal - grooves, rust patterns, riveted plates, etc.
Also you could draw grids using blood trails (gross!), ooze/tar/lava, oil, water drips, candle wax, etc.
What you want to try to avoid is a grid that is just superimposed where a lot of the squares you can't actually walk on due to architecture, or a grid on top of a grid (I've seen those too, repurposed from other games I guess).