The spell effects themselves - fire and water - are the centrepiece of the model, and I wanted bright, simple colours for both.
The fire is a basecoat of Blazing Orange (over a black undercoat, this requires about 6 coats of slightly watered-down colour to give a neat finish), highlighted first by mixing in Golden Yellow, then Golden Yellow followed by Sunburst Yellow, lastly Sunburst Yellow mixed with white.
The water is Enchanted Blue, with only two subtle highlight stages made by mixing in Ice Blue. It is given a couple of coats of watered-down Ardcoat gloss varnish to make it shiny (actually, this is applied after the whole model has been varnished in gloss, then matt).