The Heavenly Body Tier meant to birth heavenly bodies in one's Dantian.
In theory, suns and moons could also be considered heavenly bodies, but on the path of cultivation, this was different.
From the Sun Moon Tier to Heavenly Body Tier, it represented an evolution of the inner world, becoming more and more well-developed.
Just like how cultivators could fly after breaking off from gravity, this was a qualitative improvement, and flight that could traverse between planets, or even galaxies, was an even more colossal change.
The Heavenly Body Tier was like that. Even though he merely had to condense a single star now, the difficulty level was extraordinarily high. It was high enough to cause Ling Han to have to comprehend Dao underneath the Reincarnation Tree for more than 2000 "years", and only then did he attain the required understanding.
This time was not the slightest bit long.