Gu Zhen Ren
If I am understanding this correctly, the "Chaos Tribulations" that Venerables face are all of one variety as opposed to lower tribulations. That is, they must resist the Chaos outside of the world's boundary with their bodies? Because of the strength of this tribulation is life threatening to Venerables, the only way to obtain "Eternal Life" would be to become invulnerable to Chaos Tribulations to the point where you didn't even need to defend against it.
Limitless is literally limitless it seems. He goes above and beyond, a lunatic that I completely appreciate. On the topic of FY’s dao guardian, however, what if he has a clone as his dao guardian? He can mess with HW a little, and make it so (assuming a DG is required for him to gain some enlightenment) he turns his clone into his own DG.