Qi Condensation
John calmed his mind and eliminated all excess thoughts, before he sent his mind into his soul space. In the soul space existed the Primordial Extermination Lightning cultivation technique that Celestial Soulrend had given him.
As mentioned by Celestial Soulrend, there existed dantian cultivation techniques that focused on a single aspect, boosting the cultivators power in that aspect by a large amount. It acted similar to a variant body or attribute body, but was targeted to the dantian itself.
When cultivators drew Qi from their dantian out into their bodies for magical attacks, they would use their comprehension to convert the pure Qi into the type of Qi they were using to attack.