An intricate knot concerning which an oracle said that he who loosed it should master Asia, and which Alexander the Great cut through with a stroke of the sword.

【神话】哥狄阿斯结(为哥狄阿斯王所结复杂难解的绳结，神谕谓有能解此结者即为亚洲之主，而后亚力山大挥刀靳之，一刀而断)。

A problem requiting bold or daring measures to solve it.

难题；需以魄力解决的问题。