Conflict: Once on the quest the plot arc follows encounters that try the hero's strengths and weaknesses. Having decided on the hero's character, the author must create an antagonist or threat that will offer scope for the epic tale.
The antagonist in Fantasy can be a unique creation, but must hold enough recognizable traits to remain believable or plausible, even if unrealistic. If a threat looms as the major theme, the antagonist may be an inadvertent foe, a jealous companion or even a character flaw in the hero. If the antagonist is the hero's nemesis then they must hold the reader's fascination. Natural disasters, plague, famine, or destruction of a global scale brought about by an evil force are all reasonable threats in Fantasy. The scope for plotting threat is only limited by the author's ability to resolve the dilemma in a reasonable way.
As the quest begins, the plot evolves like a maze or map. Every event along the journey, every meeting with a new character, conflict or misadventure must lead toward the final climax. Even though the hero's troupe seem to diverge from the direct goal, the outcome of each scene should give a vital clue, artifact, companion or knowledge to drive the story toward the conclusion.
As the journey continues, the threat must increase. Tension is built as the importance of the quest's success increases. While romance, conflict, internal struggle and growth are part of the epic plot arc, without tension and direction toward a goal, the best Fantasy lacks the components for success.
Climax: The quest reaches the climax when antagonist and threat are faced and an outcome reached. Everything the hero has learned, gathered, or gained, is finally used in the climax. Mysteries are solved, riddles answered and developing traits in characters consolidated. Although in Fantasy, there is always an element of magic, it is not a good idea to have the threat resolved by a sudden or unexplained power solving problems that face the questing troupe. Magic must be consistent and the author should explain its use, limits and benefits during the journey, not rely on magic to solve flaws in the plot.
Denouement: Tying up all the loose ends, resolving any left over romance, conflict, need for revenge or character changes are done during the denouement. To write a successful Fantasy novel, the author must leave the reader feeling satisfied. If the story continues, as it often does in epic Fantasy novels, the author should still finalize many of the loose ends, even if an underlying quest remains unresolved.
Drive the Plot Forward: When writing Fantasy every character, every action, every scene must drive the plot forward. Avoid the temptation to delve into back-story or flashbacks and keep the story moving. Diversions, and meandering is fine as long as each setback has a logical reason revealed by the time the climax takes place.
Magic: As part of the plot must be consistent. The author must understand exactly how the power works, who can use it, how those who can't use it react to its use. Amulets, swords, healing potions are useful but should be integral to the tale not introduced to solve flaws in the plot.
Things To Do
Look over the plot of your favorite Fantasy novel. Consider how the author has contrived to create a character arc to suit the epic tale. How does the antagonist's character give scope for the hero's development? Are all the loose ends tied up satisfactorily?