After taking a single thunder, you can actually immediately undergo Divinity Transformation. Some demons transform without even enduring one thunder. But what's the point? Such a Dao Body can be shattered easily, with the Primordial Spirit directly obliterated, it's better not to cultivate at all.
Therefore, according to the usual experience of the Mystic Sect, it's more prudent to cultivate for at least a thousand years, endure three thunders, and then undergo Divinity Transformation. Each time using the Heavenly Thunder Tribulation to refine the Dao Body, obliterate the imperfect parts, and reforge and enhance. The Divinity transformed from three repeated Thunder Tribulations is quite strong. However, if you continue to endure, you risk not being able to withstand it, getting secret injuries from the thunder, and suffering a significant loss of power, making it not worth the risk.
