"Marker, present the offering."
In a shabby secret room, a deep, gravelly voice echoed by Casio's ear, as always cold and echoing.
Whoo...
A small tornado formed by the black dense fog covered half of the area, soon the airflow dissipated, the offering disappears.
"Fifteen units of Dark Source have been extracted."
"The exchangeable items are as follows..."
Without taking time to think, Casio directly chose to exchange for the power of the Secret Soul. Instantly, the sound of drizzle enveloped the secret room.
The ceiling of the secret room was covered with a layer of gray-black thick fog, like low-hanging clouds. Cold rainwater was falling, pulling silky streams that landed on Casio's body.
Instantly, a familiar sensation came from the surface of his skin. Currents of air with faint warmth were drilling into his muscles and skeleton.
This was the power of Secret Soul.