[八卦阵 / 八卦陣, bā guà zhènㄅㄚ ㄍㄨㄚˋ ㄓㄣˋ] lit. battle plan based on the eight trigrams (in legend); fig. a clever plan; a fiendishly complicated predicament#84018
[炼丹八卦炉 / 煉丹八卦爐, liàn dān bā guà lúㄌㄧㄢˋ ㄉㄢ ㄅㄚ ㄍㄨㄚˋ ㄌㄨˊ] eight trigrams furnace to cook pills of immortality; symbol of the alchemist's art; Double, double toil and trouble; Fire burn, and cauldron bubble