Andrew William Langmanis Diey (born 31 October 1973, Islington, London) is an English electronic musician, sound designer and record producer. As a solo artist, he is best known as Black Faction, or his previous moniker Foreign Terrain.
Diey first came to prominence as a musician on the Skam Records Manchester, offshoot label MASK 300, under his Foreign Terrain moniker, and later afterwards he moved onto using the more known Black Faction name for various labels.
His career as a sound designer is also noteworthy: his works have appeared in many high-profile computer games and UK television broadcasts, and also on BBC radio.