The palette is from Koffing (http://pokepalettes.com/#koffing). I just realized this is the 2nd time in a row I make something with a moon in it for a weekly challenge.
Well shit, there's actually yet another color that isn't listed... One more yellow. I wish I knew that from the start. Edit: Well, I added the 2 colors, just for the sake of completion, but they were basically completely unneeded. Bummer.
pokepalettes.com doesn't list all the colors and I think you didn't use black. Try inspecting the sprite with wouterpleizier.nl/pj/