This was a drawing experiment a few years ago. It was an ArtRage oils drawing, using colours then mainly the dry marker to subdue the strength of the original brushes. You can use a sliding scale to alter the brush sizes and strength of the metallic colours, so sometimes the colours look shiny and other times matt. It’s worth playing with different tools in apps, it increases your knowledge. I’ve found some apps really difficult to use, especially if I don’t use them very often. But I will modify what I do, and play around with things to see what results I get. I end up with a series of images, then edit out ones I don’t like. Sometimes I keep all of them so I can show how my work progresses.