I actually own the cover painting for Catastrophe's Spell, even though I've never been completely happy with it. The proportions are wrong, for one thing - Max and Haddo are way too large and the bird is far too small for one, although much of that can be explained by the need to fit them on the short dimension of a paperback cover and still have some slight idea of what you're seeing. Overall, though, not bad, and clearly a scene drawn from the book. The artist is Walter Velez.