Synonyms of riddle

1 Syllable
sphinx, strait, maze, plight, doubt, sift
2 Syllables
thrillers, stumper, thriller, twister, poser, rebus, sieved, stumpers, question, teasers, puzzle, stickler, sphinxes, unplug, teaser, puzzler, sorting, puzzlers, sieving, sphinges, sifted, sifting, problem, sorted, chillers
3 Syllables
labyrinth, cryptogram, conundrums, punctured, mystery, enigma, whodunit, braintwister, mindboggler, brainteaser, mind-twister, unstopper, mysteries, puzzlement, conundrum, charade, quandary, dilemma, brain-twister, mind-boggler, confusion, unplugging, distraction
4 Syllables
perplexity, predicament, complexity, abstruseness, intricacy, entanglement, complication, unstoppered, bewilderment, embarrassment, perplexities
5 Syllables
abstrusenesses, inscrutableness, mystification
6 Syllables
inscrutability