The Medusa was a small, but powerful, viral bug contained in a hand held box. The Medusa was created by Hexadecimal and spreads uncontrollably to everything, infecting, and turning it to stone. Soon afterwards everyone and everything infected by the Medusa degrades to dust, starting with low-energy before working up to high-energy life-forms such as Binomes and Sprites; potentially leading to the collapse of the entire system.