CONAN meets an alien

After breaking into the legendary, Tower of the Elephant, CONAN comes face to with an ancient humanoid figure with the head of an elephant. A being who explains he is from another world,

I came to this planet with others of my world, from the green planet Yag, which circles for ever in the outer fringe of this universe.

From "The Tower of the Elephant"
Page 96. "The Complete Chronicles of CONAN"