Looks like you took a grass brush of some sorta, painted it around the edge of the face, added a bit of shadow using a gradient and then applied either a texture or another paintbrush effect to the body. Doesn't fit the game at all, really.
You should have put more effort into it. Maybe instead of just using a paint brush, you could have defined the edges and certain areas of the decal with outlines of grass to add more detail.