Saleen had no certainty of being able to acquire the secrets to the chaotic void. He pressured the Heretic God and had no intentions of sparing it. He was already able to learn something regarding the Heretic God's rules by analyzing the bits of its power of the Source, and he found that to be something utterly terrifying.
Common people would not even have had a chance to die when facing off against that Heretic God. It was out to make the entire crystal wall system into his own divine kingdom, before being able to advance to crystal wall systems of higher levels.
The Lord of Glory had been a far more compassionate god in comparison.
The Heretic God was backed to a corner, so it said to Saleen, "you have to guarantee that you will never destroy all of my power of the Source. Only then will I give you the star chart."
"Relax. The words of a mage are akin to an oath. If you're willing, we can sign a contract."
