This icon presents a mainly foreground orientated appearance giving a blending transformation to an effect's tail in the background.
The fireball is noticeable as a fireball but is lacking in the fiery perspective.
Coloured in light purple, it would match an arcane missile.
The object's texture is too much scratched to give a smooth surface which a fireball should have (-> filling technique). I mainly relate this fact to the tendrils while the object's rown is decent. It could still have a nearly white little highlight on the very top.
Under the tendrils, there should be the main object, the real fireball noticeable. It's colour could be a strong red-orange. The tendrils should cover it just partially.
I don't need to tell that it's still a good icon.