Synonyms for Teaser (same or very similar meaning)
WordNet sense 1 (someone given to teasing (as by mocking or stirring curiosity)):
tease, annoyer, vexer
WordNet sense 2 (a particularly baffling problem that is said to have a correct solution):
puzzle, puzzler, mystifier
WordNet sense 3 (a flat at each side of the stage to prevent the audience from seeing into the wings):
tormentor, tormenter
From the ODE community, based on WordNet
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