In Chinese legend there are two ancient military generals who were deified and became guardians of temples. While they had proper names, they were much more popularly known as "Heng" and "Ha" - Chinese onomatopoeias emulating the sounds of exhalation through the nose and the mouth respectively. Apparently these two deities are able to exhale very deadly gases, modernly known as chemical warfare or WMD.
Shown here is (probably) Heng, as i can't really distinguish the two.