Wikipedia
Bathin
In demonology, Bathin is a duke (Great Duke according to Pseudomonarchia Daemonum) of Hell, who has under his command thirty legions of demons. He knows the virtues of precious stones and herbs, and can bring men suddenly from one country to another. He helps one attain astral projection, and takes one wherever one wants to go.
He is depicted as a strong man with the tail of a serpent, riding a pale horse.
He is mentioned in The Lesser Key of Solomon.
Other spellings: Bathym, Mathim, Marthim.