幻を追う[maboroshiwoou] to pursue an illusion
幻影[genei] phantom
幻覚[genkaku] hallucination
幻覚剤[genkakuzai] hallucinogen
幻姿[genshi] apparition

幻視[genshi] visual hallucination
幻想[gensou] illusions
幻想劇[gensougeki] non-realistic drama
幻像[genzou] phantom

鬼利死丹[kirishitan] early Japanese Christianity (from the later Muromachi period)
悪餓鬼[warugaki] brat
悪鬼[akki] evil spirit
餓鬼[gaki] brat
餓鬼大将[gakidaishou] boss of the children (in the neighbourhood) (neighborhood)

餓鬼道[gakidou] hungry ghost (preta) realm
鬼ごっこ[onigokko] game of tag
鬼火[onibi] will-o'-the-wisp
鬼才[kisai] wizard