Dungeon keys? Do you use a provided brick background, or do you create it? I always forget to ask you these questions when I see you; give me a smart tap next time! I love the keys, you always come up with the most random specimens for recreation ...... which is good!!
Well, pretty much everything in any 3D form is a "provided background." For example, things that are made of wood, or plants, or walls, or carpet have really complicated textures. To make them look real, people take real pictures and then paste them onto the objects. Then it can be made even more real by adding physical bumps that match the picture. A lot of times, I take pictures of textures I like around the house, and I use them on objects in 3D. Other textures such as water, the surface of an orange, or metal are created by hand by using different channels that define color, transparency, refraction, bump, etc. Most people have huge libraries of photographs that they use for textures, but mine is very small so you probably see the same type of wood in a lot of places!