Who is the antagonist in the whisperer in the darkness?

In H.P. Lovecraft's "The Whisperer in Darkness," the primary antagonist is the extraterrestrial entity known as the Mi-Go, a race of fungal creatures from the planet Yuggoth. They are involved in sinister activities, including the abduction of humans for their brain extraction to facilitate interstellar communication. Their motives and actions create a sense of dread and Horror, embodying the story's themes of cosmic terror and the unknown. The protagonist, Albert N. Wilmarth, ultimately confronts the chilling implications of their existence and the threat they pose to humanity.