A True Master.
They can fly through the heavens and tunnel through the earth, they can go about Refining Illusion into Truth, but the most obvious sign of all is—
For a Daoist who has reached this level, their Divine Soul has already transformed into a Yang Spirit. It can condense into a solid form in broad daylight, possessing the power to reach the clouds above and descend into the netherworld below.
Even if their physical body decays, they can use the life force of their Divine Soul to defy the natural order, reviving themselves by taking a new mortal vessel!
This heaven-defying technique is what Buddhists call 'rebirth' and Daoists call 'Reincarnation'.
But to put it bluntly, it's Possession!
Legend has it that a True Master once waited for a powerhouse with a Title to be on the verge of death. The True Master then seized their body and spent a decade of secluded cultivation tempering it.
