Maurice de Jong (born 5 September 1973), known by his moniker Mories, is a Dutch composer and musician. He is best recognized for his multiple music projects, namely Gnaw Their Tongues, Seirom, Aderlating, Cloak of Altering and De Magia Veterum. His compositions are informed by ambient music, black metal, drone music, electronic music and the avant-garde. His interests lie in invoking a disquieting and nightmarish atmosphere with his music, which often utilizes distortion and dissonance. Lauded as a most prolific composer, de Jong has recorded an upwards of three albums per year since 2007.