Someone who likes to play jokes or tell fibs is a trickster. If you're a trickster, your favorite holiday is probably April Fools' Day.
While we commonly use the noun trickster for anyone who plays pranks or cons you out of a dollar, the trickster is also a classic character in mythology and folklore. These trickster figures are usually smart and canny rule breakers. In Greek mythology, Hermes is often seen as a trickster, and in West African stories, a spider named Anansi is the epitome of the trickster.