Zerix is the deadliest of all fungi. He is widely known as the "Emperor of the Fungi". His appearance ushered in the end of the Cenozoic and the beginning of the "Age of Fungi". It is unknown what variety of fungus Zerix evolved from, but from his appearance, one can infer that his ancestor species was some variety of mushroom. Contrary to popular lore, Zerix did not evolve from Armillaria ostoyae. Zerix relocated his base of operations from Zenzar Forest into space after an SXDI attack on Zenzar Forest. He suffered his first death aboard the Imperial Space Fortress at the hands of John Sitnaf.
Unlike most fungi, Zerix may not be a carbon-based life form (CBLF). This has been inferred by his referral to John Sitnaf as a "puny carbon-based life form".