It has been observed that Robert E. Howard made his best use of Lovecraft's mythology when he used it as the cosmological backdrop for his sword-and-sorcery tales. One of the clearest examples of this occurs in Howard's story "The Tower of the Elephant", wherein Conan the Cimmerian penetrates the defenses of said tower hoping to procure the fabled gem within. In the process, he encounters an imprisoned alien from another world --- Yag-kosha, whose green-skinned form is humanoid save for having the head of an elephant. (Once he possessed wings as well, but these have since withered away.)

Yag-kosha has been imprisoned and tortured by an evil Zamoran magus who seeks ever more of his occult knowledge. The fortuitous appearance of the Cimmerian, however, offers Yag-kosha a chance for deliverance. He pleads for Conan to slay him, since a sword-stroke will liberate him from his broken physical form like a butterfly from its cocoon. Thus reborn, Yag-kosha gains his revenge on his human tormentor, and Conan narrowly escapes the destruction of the "Tower of the Elephant".

Two things are to be noted here. First, the idea of the minotaur-like alien is borrowed wholesale from Lovecraft. Yag-kosha explains, "Long ago I came to this planet with others of my world, from the green planet Yag, which circles forever in the outer fringe of this universe. We swept through space on mighty wings that drove us through the cosmos quicker than light. . . . We saw men grow from the ape and build the shining cities of Valusia, Kamelia, Commoria, and their sisters." This is all too reminiscent of Lovecraft's "Elder Ones" of Antarctica, his "Great Race" of Australia, and especially his "Outer Ones" in the Vermont woods. These crustacean-like aliens even had similar ether-beating wings. And Howard's alien planet "Yag" sounds suspiciously similar to their world "Yuggoth" (as well as "Yaddith", "Yith", "Yig", "Yeb", and "Yog-Sothoth", but who's counting?).

Second, it is apparent that Howard has not merely copied HPL's visitors "out of space" to use them as stage props. It is not as if any old dragon or gorilla would have sufficed. As a matter of fact, Conan does fight off a giant spider in the same story. By contrast, his encounter with the Elephant Man from Yag is handled altogether differently. Whereas, so to speak, the spider is there for Conan's sake, to test his mettle, Conan himself is there for Yag-kosha's sake. At the climax of the tale, Conan is shunted out of the spotlight to take a supporting role. The resolution of the story is Yag-kosha's revenge, in which Conan is simply an accessory.

The point of all this is that Howard not only used Lovecraft's standard aliens, but also used them in a manner altogether consonant with Lovecraft's. Once the alien enters the story, he dominates it, symbolizing the inbreaking of the Infinite Beyond which dwarfs man. Just as Lovecraft believed that the vastness of the universe dethrones man from his illusions of anthropocentricity, even so Yag-kosha displaces Conan, hitherto the hero, but now relegated to a "bit-player". The Cimmerian stumbles onto some thing much bigger than himself, plays the small part blind luck has assigned him, and is lucky to escape with his life.

In light of all this, one might even enumerate Howard's "The Tower of the Elephant" among his Cthulhu Mythos stories.