In a sense, Xiu and Taotie had something in common, and that was devouring.
Xiu could devour the power of the Devil Clan to destroy it, but Taotie could absorb it bit by bit.
"He will never be full, but he can allow his strength to reach the peak. Once he reaches the peak, he will break through the shackles of hunger and unleash his true strength. The reason why he possesses the aura of a holy beast is also because he has absorbed a portion of the power of the Tree of Life. However, this power is only enough for his source to reach the level of a holy beast. If he wants to transform into a real holy beast, he will need to replenish more energy. He is a magical beast that requires constant recharging in order to unleash its destructive power. Once he absorbs enough power, not to mention a holy beast, he can even stand toe to toe with a legendary magical beast." Xiu understood Taotie very well because he was the only one in the world with similar attributes as him.