Epic fantasy contains many words. A typical epic fantasy book exceeds 100,000 words. They are not quick reads. Their length requires a solid commitment from the reader.
Example: The Lord of the Rings contains about 473,000 words.
Epic fantasy contains many absolutes. The villain is an absolute evil. Characters can usually be divided into good and evil. The villain has one master plan. His followers are absolutely loyal. The magic sword is absolutely needed to defeat the villain.
Example: In Lord of the Rings, many characters are absolutely evil, such as Sauron, Grima Wormtongue, and the Balrog. Other characters are absolutely good, such as Galdalf, Aragorn, and Elrond. The One Ring is absolutely evil and almost absolutely indestructible. Sauron's armies are absolutely unbeatable.
Epic fantasies are impersonal. Although the villain may have some sort of personal relationship with the hero, for the most part, the villain's taking over because that's what he wants to do. For the most part, the villain represents an impersonal danger to the average Joe. Likewise, the heroes are running about helping people in order to stop the villain. They help people along the way because they happen to be there, not because of personal relationships.
Examples: Sauron isn't conquering the world due to a spat with somebody. No apologies will stop anything. He raises his army to kill and conquer because that's his goal.
Epic fantasies characters interact formally over familiarly, especially around leaders. Introductions, state talk, and alliances often produce stiff dialog. Words have consequences in such literature, and so must be used very carefully.
Example: Gandalf speaks to King Theoden. Gandalf speaks to Saruman. The meeting of good people at Elrond's house. Galadriel's meeting with the fellowship. The Entmoot.
Ceremony is important in epic fantasy. Ceremonies are often used to mark important occasions. Ruining a ceremony has great consequences.
Examples: The forming of the fellowship. Galadriel's mirror. Bilbo's 111th birthday party speech.
Societies in epic fantasies are monolithic. Each society exists, has existed as it has existed for hundreds, if not thousands of years. These societies live next to each other, but never seem to influence each other. Each society has its own tradition, which do not transfer to other societies.
Examples: Dwarves and elves have lived unchanged for centuries. Gondor has no king and hasn't had one for over a thousand years, yet they still expect one to show up one day. Every society is very segregated.
Epic fantasies put great weight on what is right and proper, and what is right and proper exists objectively. Many epics feature the right and proper king to take a throne. The villain is usually not the right and proper ruler, and so represents a great wrong. Putting things to rights are important actions within the work.
Examples: The cleansing of the Shire. The restoration of Theoden.
In the end, philosophical conflict devolves into physical conflict. In the end, the final physical conflict is intertwined with the resolution of the philosophical conflict.
Example: Aragorn leads the final battle against Mordor while Frodo fights Gollum for the One Ring. The destruction of the One Ring resolves all battles.
The threat to the kingdom or civilization comes from the outside, not the inside. The outside threat is uncivilized and uncontrolled.
The world contained an ancient past that was better/greater/more learned/more magical than now.
Example: In Lord of the Rings, this is the Third Age of the world. Two great ages came before now.
The foreigner corrupts your allies. Often the foreigner has destroyed civilizations from the inside before. To ally with the outsider is to become corrupted.
Examples: Sauron corrupts Saruman. Sauron once corrupted the Dunedain by living among them. Sauron fooled the peoples of Middle Earth, using his magic rings as tricks. Wormtongue corrupts Theoden.
Magic is present, but not omnipresent. Magic does not erase sweat equity.
Examples: Gandalf does magic sometimes, but most of the time, he does no magic at all. He walks like everyone else. Sauron uses foot troops to enforce his power.
The usurping enemies are cruder, more childlike, dumber, and far more like the lower classes. The rightful people people act and behave as the upper classes. Rightful peoples display admirable traits.
Examples: Orcs speak brutally and eat people. They stink. They have little hierarchy aside from brute force. Their weapons and armors are crude. Elves are pretty. Humans are noble. Dwarves are steadfast. Hobbits are earnest and earthy.
Ancient and unique objects are held or sought by the various factions.
Example: The One Ring. Aragorn's sword. The Palantir. Galadriel's Phial.
How well does this hold up? That's up for you to decide. Grab you favorite epic fantasy and test my observations. Do they hold up? Which ones don't hold up? Which ones did I miss? Join the fun.