Krejin felt like his whole world is collapsing.
He should have understood that something is wrong when he saw Sam alone in the middle of nowhere. How could someone who created so much destruction and showcases so much of his abilities, even managed to escape from the shadow cavalry with just a flash of light be so easy to find? Why didn't Krejin even stop to question himself about this?
He just lost himself in his complacency.
And complacency lead to the death of Siola. That's right, the bloody mess on the ground right now is Siola and the soul that he just absorbed also belonged to her.
As for how it happened... it is very simple. The pill that Sam drove into Siola's mouth played a key part. It is the disguise serum that he created. This one is not really a perfect serum like the ones he has given to the managers. Instead, it is a prototype.