I did 5 today (3 need more work) including an ink sketch of Leonard Bernstein on enamel.

I have gilding stuff that applies like shoe polish and all sorts of powdered pigment. I have some Escher prints that use chrome paper for the white and ink for the black.

I did use a mirror poster paper today with transparent paint.
It is predictably very metallic looking.
Outside I thought I would try setting the volitile transparent paint on fire. Poof the flames went over a foot high. I titled that one big bang.
A huge red O'Keefe like rose was too pretty to set on fire.

Most oil paints can be made to be transparent