Book of Fiends, Volume One: Legions of Hell is a 2001 role-playing game supplement published by Green Ronin Publishing.
Book of Fiends, Volume One: Legions of Hell is a supplement in which devils are detailed. [1] [2]
Shannon Appelcline noted that "In 2001 Green Ronin expanded beyond their early Freeport adventures and went into the business that the more successful d20 publishers were already in: publishing sourcebooks and other gaming material. This began with the well-received monster manual, Legions of Hell: Book of Fiends, Volume One (2001)." [3] : 371