Quite recently, as part of an assignment, we had to create a training environment for Hydrogen Cell Bus Mechanics. Other than the general team organisation, I was able to take part in bringing fantasy to the game. So I took some of the models my teammates created, added a little Ivy and gave it a mossy rock texture to give it the look of an otherworldly author.
I loved giving the environment a story especially as this was not a story-based game, yet these fantasy-like visuals give it a sense of epic mystery. Wonder what the story could be...