As with other Monster Manual supplements, MM4 contains a variety of new creatures as well as expanded variants on staple D&D monsters such as orcs, demons, yuan-ti, and gnolls. What separates it from past volumes is the level of detail given to each creature subtype, including probable behavior in combat and even a complete pre-prepared encounter complete with a map.
Like other Monster Manual supplements, MM4 features a diverse array of new creatures as well as enhanced versions of classic D&D monsters such as orcs, demons, yuan-ti, and gnolls. What distinguishes it from previous volumes is the level of detail provided to each creature subtype, including likely behavior in combat and an entire pre-prepared encounter complete with a map.