Cthulhu, the great sleeper from the stars, is the most popular and recurring Lovecraftian "mountainous monstrosity" in horror literature. But what other disturbing beings run through the stories of the great master of fantastic literature? This Bestiary is an interpretive exercise, full of hints, that brings together twenty-two terrifying creatures represented by Enrique Alcatena, completed with extracts from the capital works of H. P. Lovecraft: a masterful descent into the abysses of terror. Mushrooms of Yuggoth, the Nocturnes, The Tsathoggua or the Shoggoths, among others, are the protagonists of this panoramic atmosphere of fear by the American writer, which surpasses previous literary manifestations of the phantasmagorical and the bloody. Influenced by the macabre and sinister atmosphere of Edgar Allan Poe, Lovecraft, creator of the current of cosmic horror, goes beyond classic terror and expands the reader's imagination by appealing to the unspeakable; the fear generated by the incomprehensibility of events of an indescribable nature: «There are no words to describe such abysses of strident and immemorial madness, nor such terrifying contradictions of all the laws of matter, force and cosmic order», (The call of Cthulhu). Unknown forces, alien to the laws of nature and permanently veiled figurations claim the pictorial language of Alcatena's prints.