The mycon were initially approached by the Chenjesu and joined the Alliance.  After several clashes with the Hierarchy, the mycon sent a delegation to the Ur-Quan and voluntarily joined their Hierarchy of Battle Thralls.

    While many are baffled by the so-called "Betrayal of the Mycon," a careful study of the Mycon culture can provide us with an explanation. The mycon have been know to say that Juffo-Wup acknowledges the existence of un-Voidable Non. When they are faced with such, they join, absorb and wait for their opportunity to learn the weakness that will allow them to Void the Non. Clearly the Alliance was one such un-Voidable Non.  After having joined the Alliance, the Mycon learned what they needed to know. The strength exhibited by the Ur-Quan and their Battle Thralls was just what the Mycon needed to Void the Alliance. The result is well-known to history.