Same word as phantasmagoric:

apparent, blue-sky, chimeric, chimerical, deceitful, delusive, delusory, dreamlike, fake, fallacious, fanciful, fantastic, fictional, fictitious, fictive, hallucinatory, ideal, illusory, imaginary, misleading, mistaken, ostensible, phantasmal, phantasmic, pseudo, seeming, semblant, sham, suppositious, unreal, untrue, visionary, whimsical