Although they were all quite enthusiastic about becoming Divine Creatures, Isaac had unfortunately given Mephisto the Virtual Divinity of a True God, not an Evil God, so he couldn't create Followers without limit.
In other words, they had to meet certain conditions or complete Trials to be granted power by Him.
Naturally, their numbers couldn't compare to the indiscriminately created Followers of an Evil God, but their quality was much higher. Their combat power, Life Force, and even potential far surpassed those of an Evil God's Followers.
Furthermore, they would retain their free will for a relatively longer time. Unlike the Followers of an Evil God, who, if lucky, might last seven or eight years, the unlucky ones would be completely lost to Corruption in three to five years, or even less than one.
