a.k.a. The Pallid Mask Mug by Horror in Clay, Hastur from the Cthulhu Mythos Mug
A mug depicting the King in Yellow (Hastur the Unspeakable). It is glazed in yellow with a reddish antiqued wipe-away effect. Hastur is the name of a deity created by Ambrose Bierce and later incorporated in the writings of Robert W. Chambers and other authors, eventually forming part of the Cthulhu Mythos. In its original appearance in the 1893 short story "Haïta the Shepherd", by Ambrose Bierce, Hastur is a benevolent, bucolic deity worshiped by the title character. In The King in Yellow, In Robert W. Chamber's 1895 collection The King in Yellow - which contains stories related to the titular (and fictional) play, the name Hastur shows up multiple times, but in different contexts, referring to either a character or a place. The King in Yellow is often depicted as a creepy figure in tattered yellow robes with a mysterious pallid mask on its hooded head and sometimes hands (but sometimes tentacles) protruding from deep sleeves.