Starting from the Black undercoat and using the limited palate I have decided on in other posts.
I hope to do a pattern close to a Tesler tower with sparks climbing cross ways up the length of the blade towards the tip. The edges will be bright but brightest where the sparks hit the edge.
This is the same method some folks used to use on Gemstones, comming up from black to light.

1) Start with Spacewolves Grey and line those points and edges where the power sparks will be brightest. Include the cross ways sparks.

2) Thin Blood Red to watery. Add it in many thin layers concentrating on the areas around the Spacewolves grey area. I am seeking a 'Gausian Blur' look. Continue at least until the Spacewolves Grey lines cannot be discerned.

3) Thin Sunburst Yellow to watery. Mix a little of this with the watery Blood Red to get an orange. Using this, add highlights on the powersparks and edges where the sparks hit the edge.

4) Mix a little of more of the Thin Sunburst Yellow with the watery Blood Red to get a brighter orange. Using this, add smaller highlights on the powersparks and edges where the sparks hit the edge. This is where I stopped.