abstruse, alchemistic, arcane, astrological, baffling,
cabalistic, covert, cryptic, curious, dark, difficult, enigmatic,
enigmatical, equivocal, esoteric, furtive, hidden, impenetrable,
incomprehensible, inexplicable, inscrutable, insoluble, magical,
mystical, mystifying, necromantic, obscure, occult, oracular,
perplexing, puzzling, recondite, secretive, sphinxlike, spiritual,
strange, subjective, symbolic, transcendental, uncanny,
unfathomable, unknowable, unknown, unnatural, veiled, weird .