Firion sprite

Yeah, as I suspected this sprite was likely saved as a .jpg at some point, so it obviously was converted into a bunch of colors. To get it to work you would have to manually recolorize the sprite until the sprite had 18 colors (16 + Black and Transparent).
That Firion barely looks like Firion though, your best bet is probably looking for something better.

Yeah, it was easier to find Firion sprite than to ask someone for help with this little one. By the way, I looked into your sprites, may I ask, what sprite are you going to do next?