Gouache is a water-based paint that is opaque and matte, similar to watercolor but more opaque. In gouache, pigments are ground up into a powder, but not as finely as watercolor. The pigments are combined with a binder, therefore, compared to watercolor, the paint is more densely packed with pigment. I love gouache because of its vibrant opaque colours like in this painting. I have used Posca Marker Pens for some of the detail. These contain a water-based acrylic paint that is highly pigmented, opaque and matte, hence the vibrant pop of colours in the detail.