Synonyms for Prankster:

n.

humorist (noun)
essayist, author, actor, scriptwriter, dramatist, columnist, wit, belletrist, card, jester, gagman, comedian, word smith, Banterer, funnyman, buffoon, comic, cutup, playwright, humorist, copywriter, punster, clown, joker, wag, writer.
mischief (noun)
rogue, scamp, rascal, imp.
prankster (noun)
tricker, trickster, practical joker, hoaxer.

Other synonyms:

laughing stock, good-time Charlie. rogue, scamp, rascal, imp. mischief. Other relevant words:
practical joker, hoaxer, imp, rascal, rogue, scamp, mischief, trickster, tricker.