I could have gone with historical novel but I chose HYPERBOLE-- which is pure and simple exaggeration. It can be used to heighten effect, or for humor. Shakespeare employed HYPERBOLE extensively. Children's books often use it with great success. Think the Lemony Snicket Series of Unfortunate Events books, and anything by Roald Dahl.
(This post has been inspired by and in some instances, directly quoted from A Handbook to Literature, 8th Edition, by William Harmon and C. Hugh Holman)