Entities, or Monsters, are entities which vary in severity from being harmless under specific conditions to hostile no matter what, and serve as the primary antagonistic force in Interminable Rooms. Most of the entities that roam their respective section serve as the main threat and hinder the player's goal to progress further into the rooms and vary in the kinds of mechanics they possess. The numerous entities and their various traits are a famous staple of Interminable Rooms and have defined the game very well.