These are the new monsters who appear in the Hellfire expansion.
The Hive[]
The Crypt[]
Bosses[]
Bestiary
Diablo I Bestiary • Hellfire Bestiary
Diablo II Bestiary — Act I Bestiary • Act II Bestiary • Act III Bestiary • Act IV Bestiary • Act V Bestiary • Unused Bestiary
Diablo III Bestiary — Act I Bestiary • Act II Bestiary • Act III Bestiary • Act IV Bestiary