Lightning based blaster build?

[Unoriginal]

So if wanting to build a lightningmancer, what classes, races etc would be best? Thinking something like Owlin 2 level tempest cleric, rest draconic sorcerer that chooses lightning damage, pick metamagic that transmutes elemental damage from say fire to lightning & then go to town with max damage fire/lightning balls?

Sounds like you got everything for a build.

Probably better to start as a Draconic Sorcerer, though, and take the Cleric levels after 6 levels of Sorcerer.