Slippery, literally and figuratively.
Like all Illidiths, Karasith began as a tadpole swimming in the pool of an Elder Brain. After being inserted into the body of a notorious crime lord, he quickly realized that he had far more to gain using both his psychic gift and the power and influence of organized crime.
He let a coup against the elder brain, enslaved the minds of those he couldn’t convert, and kept the resulting Neothelid as a pet.
Disappointed with the current situation, he has taken residency on the Eye. Making a name for himself by contributing heavily in the slaying of the “chromatic dragon infestation”, he has made his business in dealing with drugs and other consumables.
There goes a saying:
If Karasith’s drugs fail to unravel your mind’s secret’s, Karasith himself will.