Lightning Tribulation Golden Core Refinement?

"Is he crazy? He actually spat out the Golden Core under the lightning tribulation! Wait a minute! When did he become a Golden Core cultivator!"

As soon as the lightning tribulation began, the three elders of the Scripture Storage Valley immediately rode their artifacts and flew out of the city.

At this moment, they saw the rebel cultivator, Duan Shuang, flying into the sky while enduring the lightning tribulation. While they gritted their teeth, they also had a strong sense of doubt.

Exposing the most important Golden Core directly under the lightning tribulation was no different from courting death!

If his Golden Core was destroyed, what was the use of having a physical body?

Furthermore, in the sect's records, Elder Duan Shuang was only in the True Core realm a few days ago. How did he become a Golden Core cultivator in just a few days?