Even Marvin hadn't thought that he would get such extensive benefits when he made the decision to enter the Crypt Monster's mouth!
The Crypt Monster killed everything around him, and the essences were then cleanly harvested by Marvin's Essence Absorption System.
This trip resulted in the Crypt Monster storming the Black Dragon God's nest and allowing Marvin to find an unguarded Faith Pool!
This was like a huge gift dropping out of the sky into his arms, and Marvin couldn't refuse it even if he wanted to!
It was so rare to find a God's secondary plane so unguarded.
If not for the Astral Beast's attack, Marvin would have never gotten such an opportunity.
He naturally understood all of that. But he couldn't leave this place without visiting the Faith Pool. After coming this far, how could he leave it for the Black Dragon God?