Republica IV is an enormous gas giant in plain view from Republica, Republica II, and Republica I, the three most important planets in the system of Republica. The planet is mainly one constant chemical reaction of sulfur, hydrogen, and clouds of chloride. When these chloride-clouds hit the atmosphere they display fantastic light shows. Because of the dense population in this system (over 13 billion), there are many tourists traveling to nearby coordinates to view these cloudbursts as well as the impact of space-debris as it is pulled into the atmosphere and burns up with thousands of kilometers-long shears of light. This form of tourism reaches its peak every 181 years with the coming of a group of comets that pass by with some of them plunging into the planetary atmosphere, leaving the spectators in awe of these enormous, universe-shaping forces.

Republica IV has always been a cause for ancient rituals and beliefs. When space-exploration was not yet developed many inexplicable situations were accounted to this planet. Scrolls found on Republica II indicate Republica IV was once regarded as a god. When mankind started to explore space, the Aravathor-cult lost its reason to exist and people started to take to more rational ways of thinking. Superstition, however, is still widespread in the culture of the inhabitants of Republica. Republica IV is still found in many old sayings and legends in this system.