I must say that this piece is excellent. The technique, as yours always is, is stunning. The background to the scene makes sense; maneuvering an Arwing in a mine wouldn't work, same with the Landmaster. The originality of Krystal's appearance is, for lack of a better word, epic.
Now, onward to the overall appearance. The splash is very realistic, as is the ripple alongside it. The appearance of the flash of Krystal's staff on the water is also very original. It is, in fact, so original that I have only ever seen you able to do it. I also find the fact that Krystal is covered in dirt realistic, as she would come out clean after being involved in a rockfall.
This is the last thing I have to say is the few problems I have with this. I know she is running away from enemies, but she still has an awkward pose. My main problem is with the staff though. She is holding it with her left arm fully extended out, meaning she would only get one shot off at an enemy before she would have to re-adjust her arms to be able to shoot another enemy behind her. Being that she has combat training, she wouldn't hold it like that.
The second problem is the originality. Krystal is almost always depicted as a damsel in distress with no help in sight. I find that the originality of Krystal herself and the enemies around her evens it out a bit.
Taking all of this into consideration, I would say this is a great piece that is on par with all of your other artwork.