Looking at the motionless behemoth not far away, Dong Tianyu actually felt an impulse to directly take it into the Cave. If he could dismantle this enormous being, he should be able to advance the upgrade progress of the Cave to some extent.
Now, Dong Tianyu had also figured out that what the Cave needed for an upgrade was not some specific material, but carriers containing various energies.
Under normal circumstances, although those ancient creatures do not cultivate actively and can only passively absorb the nature's spiritual energy present in the air, the bigger the ancient creature is, the more Spirit Energy it absorbs in the same amount of time.
This is why the larger the ancient creature is, the stronger its inherent defense.
However, the behemoth not far away, even if not categorized as a gigantic ancient creature, was at the very least a top-tier species between large and gigantic ancient creatures.