Infinite Evolution Triggered, Acquired [the Continuous Flow of Life]
The reason for Sterl's excitement was that—BOSS had appeared!
Moreover, he discovered several BOSSes of various forms.
The Breath of Transformation and Soul Solidification Gem that Sterl needed, along with the Sky Curtain Core for his quest, were all produced by the various BOSSes in the Heavenly Curtain Canyon.
These BOSSes had vastly different skills and attributes, but they were all special life forms that accumulated energy through the Sky Curtain Core.
Therefore, while the loot varied, there were common drops—specifically, the Breath of Transformation and the Soul Solidification Gem.
To activate the Blood Sacrifice Array and establish four sub-arrays, Sterl needed four Breath of Transformation and the domain of Soul Solidification. Now, he had already discovered three BOSSes.