Unblack metal is simply black metal with Christian lyrics. The term comes from one of the first unblack metal albums, Hellig Usvart (which means Holy Unblack), by Horde, released in 1994. The most notable bands in this genre are Antestor, Crimson Moonlight, Horde, Slechtvalk and Drottnar. The entire movement has faced opposition from Christians and secular/satanic bands as well. It's still a very controversial genre, although it's a lot more accepted than it was back in the 1990's.