Thunder Bolt can be used for attunement chakra opening and treatments. These functions are now being divided between Thunder Bolt and Serpent.
Thunder Bolt is now used for attunements and to intensify the power going into a treatment area. It is drawn top to bottom. Think of it as pulling healing energy down from the divine source and directing it intensely to the area where the bolt hits. The intensity of the healing then becomes like the intensity of healing that one gains from being attuned.
In ancient times the Thunder Bolt was used in reversed direction, drawn from bottom to top, to direct energy up from where it is psychically rooted in the spine toward heaven. The result was that the recipient would become more aware and awake to higher energies, becoming more enlightened.