First we start with base background, that will be used later for created many variants of environment.
Then, we add exits on four corners of room.
...And we crop them. There can be any arrangement of exits.
Then we can start working on another variant
...And also add exits there
Now, after we have two background, we can do mashup. We start with gradient mask, and later we paint over details. Also, it's good to move things around for variety.
We also reuse previous exits, match them & overpaint if needed.
And it's time for another variant. For this one, we used one of previously existing backgrounds, matched color and overpainted it.
This is base art we borrowed from. With large database of artworks we did over the years, we can do lot of creative mashups.
With three base variants, we can create even more mixes.
Environmental assets for Dungeoneers, with creative process explained step by step.