Entities are creatures from netherwolrlds like heaven and hell, places strongly aligned with some philosophy or other. Themost commonly encountered enteties are demons, but there are numerous types of entities, and some of them are not evil.
All entities have the following Limitations: Dogma, Spirit, Supernatural Creature. They are fully affected by Summoning. Most have more limitations, but they are too diverse as a group to offer any general guidelines.
Celestials
These are the spirits of good, also known as angels, devas, bhodisatvas or by a host of other religion-specific names.
Demons
The hordes of the abyss are demons; vile and evil creatures who contanty strive to improve themselves at any cost. Unorganized bullies, demons rarely form a coherent plan or society, but are individually very dangerous. Few demons look alike.
Devils
The legions of hell are made up of devils. Unlike demions, they have a definite hierarchy. They will cajole and bargain when they are weak, but quickly turn into tyrants when they have the advantage. Devils form legions and hosts of similiar creatures, with officers and a chain of command. However, being evil, they will try to subvert even the orders of a higher-ranking devil for their own advantage if they can.