Anansi

Anansi, god of cunning and spiders.
First appeared in Season 2, in Episode 13: Anansi.
Duped Dewey Kiesling and Simon Prince as a way to infect Clearwater with water of the Styx, creating a nightmare infestation of spiders from small to giant size.
This was part of a plot with Erebus, for whom Anansi was acting as an agent.
Killed by Fionn Corvin.