The Mycon are a race of creatures that nest near the Brahe and Scorpii constallations. While most sentient races (with notable exceptions) are taxonomically animals, the Mycon are fungi. To Humans Mycon living conditions would be most accurately described as "hellish", with temperatures close to the melting point of lead.
Conversations with the Mycon are very difficult, only the Orz could be considered more confusing and even that would be up to debate. The Mycon constantly ramble about Juffo-Wup, the Non and the Void with vaguely religious overtones and often as a complete non sequitur to the topic at hand. They are usually very hostile toward other species, even other Battle Thralls. However they are the only known race to actively seek out the Ur-Quan in order to join The Hierarchy and have always treated that race with respect.
The Mycon colonize words through agressive terraforming. They launch their Deep Children into the crust of the planet's surface where its tendrils grow, molding the enviroment of the planet to the Mycon's liking with terrible tectonic movement and volcanic activity — it becomes a Shattered World. Mycon prefer warm, living Water Worlds in which to plant these seeds. One victim of this activity was Syra, the Syreen's homeworld.
The Mycon spread the spores of their race through the galaxy with their Podships.