I'm planning on experimenting with the different suggested palettes in Suzanne Brooker's Portrait Painting Atelier (book discussed in this post of mine). This is the first one: viridian toned, then a limited palette of viridian, alizarin, raw umber, and lead white. (Raw umber oil paint is very bizarre to me: it feels like painting with lumps of wet dirt...which I guess it is, actually.) It took until it was about halfway done for me to decide not to scrape it, and to keep going; at first, it seemed the palette was going to be impossible...then all of a sudden it began resolving and I'm pleased with it. The likeness is fairly close, though you can see I didn't sketch it out much first. This was about an hour and a half, alla prima with a mirror.
I may have the strangest cat in the world. (I once saw a bumper sticker that said My cat is weirder than yours.) I think he looks like a snake here (no ears).