Brian Vannatta is a level designer. He was also the designer of Harm for Duke Nukem 3D.
Vannatta is most notable for his Doom levels, especially JUDAS23, the 23rd level of the JUDAS series. Vannatta continued his work on Quake, adding a 24th level to the series with Judas24 v1.0.
He was also co-author of the Igor and Danzig series