The details are wonderful; ice is so very rigid and sharp, though you have the whorls of snow crystals, whereas the fire here is very liquid. Both layer nicely. The Fire Princess would seem to have the upper hand initially, as she is clearly damaging the Ice Queen's mien, yet those claws of the Queen's look formidable, as does the array of shards that seem ready to strike from the right.
Other touches I enjoy are the smoke billowing up in the upper left and the jet of flame rocketing the Flame Princess upwards. The style also holds well with that of the show they originate from, and both look quite fierce. The flames and ice together do a superb job of directing the viewer's eye in toward the center immediately, where the focal point is. Fire and Ice isn't an original idea, nor is having them square off, but this is done extremely well.