The Verifex Explosion in the M50 cluster in Monoceros left numerous systems scourged and devoid of life; the reclamation of this volume is generally known as the Hellfire Expansion
Also known as the Monoceros Reclamation Frontier, or Gehenna Resettlement Sphere, the Hellfire Expansion is the popular name amongst the NoCoZo pioneers streaming into the area affected by the Gehenna Incident. The Gehenna Incident and its aftermath left many worlds scourged, and devoid of life, but left behind the wormholes and most of the high-tech worlds that didn't reside too close to the incident. This caused a rush of pioneers and entrepreneurs which used the still standing wormholes to quickly get into the catastrophe area behind the radiation wavefront, and resettle the systems which had been rendered devoid of life. While most of the pioneers origin from NoCoZo, there are also a large number of pioneers from the Version Tree, Sophic League and Orion Federation, as well as a smaller inrush of pioneers from almost anywhere else.
The result is a huge mix of cultures. Sophic Monks of the Solitude can be found in the same system as memestrong version tree neumann. Asteroid herders from NoCoZo rub elbows with Orion propagandists. Conflicts are common, but so is unusual cooperations.
Different from most other mobile frontiers, is also the fact that many of the pioneers have moved into the area for profit rather than solitude. Whether that profit is economical, territorial or spiritual, there is an enormous amount of interaction between the various systems and clades, as well as the high tech systems and wormholes, which provide information and high tech goods to the center of the cooking pot.
However, the fact is that the Hellfire Expansion has no true frontier. Enclosed on all sides, and seeded throughout its volume with wormholes, the mobile frontier will be consumed sooner or later as the empires around it gobble up the territory, with nowhere for the pioneers to go. During the 3100 years since the Gehenna Incident, the Orion Federation as well as NoCoZo has steadily annexed worlds, with a dribble falling to the Version Tree, Sophic League and polities farther away. Though the Hellfire Expansion still seems to be going strong, it is the truth that it is on its last legs. Many of the worlds that seem the most frontier-like have actually already signed treaties with the NoCoZo, and the pioneers there moved on to more open frontiers.