"This is the gulag Rura Maxis. There is no stockade. No guard tower. And no electronic frontier on this planet. Only a magnetic shield prevents beaming. Punishment for the most hardened and most dangerous prisoners means exile from prison to the surface. On the surface, nothing and I mean nothing can survive without proper weather gear and food. It is much warmer underground. Work well, and you will be treated well. Work badly, work weakly, work terribly, and the most tough and most dangerous of you will die."
Rura Maxis was a penal colony planet utilized by the Irken Republic (reformed Irken Empire under Tallest ZIM). Located in the Theta Penthe system, it was widely known as "the alien's graveyard," due to the fact that the life expectancy for a prisoner there was, at most, one year. Tallest ZIM considered sending former-Tallest Red and Purple here as part of their banishment, but thought against it as Foodcourtia seemed to be a more fitting punishment for the freeloading despots. (The same thing occurred with ZIM himself when he was being sentenced for the crime of murder during Operation Impending Doom I; however, somehow the Control Brains knew that someday ZIM would be redeemed and secretly gave him a way to escape, creating the first step to his perfect future). The Irkens in the past however did not consider mining a particularly "honorable" task and therefore delegated it to political prisoners or victims of their conquest.
The colony was overseen by a Irken warden who would give a speech explaining the working conditions of the gulag to arriving prisoners and inform them of the colony's only known punishment for hardened prisoners only, "exile to the surface", where they would freeze to death in a matter of minutes without proper weather gear and food. If prisoners worked hard and well, they would be treated well and punished if they didn't.
The mines are based on the Rura Penthe mines from Star Trek VI: The Undiscovered Country, the Cobalt Mines of Shokan from Mortal Kombat: Conquest, and the Spice Mines of Kessel from the Star Wars metaseries. The planet was inspired by Hoth from Star Wars and Rura Penthe from Star Trek, as both are ice planets like Rura Maxis.
Prisoners at Rura Maxis were forced to conduct mining operations for the purpose of retrieving the vast deposits of trilenium which existed beneath the surface. The surface temperature of Rura Maxis was extremely low, the landscape dominated by glaciers and gusting snow. Without proper clothing, warmth or food, no life form was able to survive for an extended period on the surface (a condition often used to punish rough-and-tough prisoners), so most of the mining and prison facility was located underground where it was much warmer. A magnetic shield encased the mining facility and a vast area surrounding it in order to prevent escape through beaming from the surface. The facility was routinely patrolled by armed guards, but further security measures were deemed unnecessary due to the harsh surface climate.
The most common form of punishment given to only the most dangerous prisoners is banishment to the freezing surface, where again they don't survive for long without the proper weather gear and food. One of the prison's commandants made a point of banishing at least one troublemaker each time that new prisoners arrived, so that they would know from the start the penalty for working badly, mistreating fellow prisoners or disobeying the rules.
Food provided to most prisoners in the mines is some kind of meaty soup or stew served in a clay or ceramic bowl, but other foods are available, such as wolf-boar burgers. The food is cooked over a warm fire.
Prisoners are dragged to lower levels of the Mines in chains, being led by guards that seem to resemble Irken palace guards (as they hold shock spears). Chains also hang from the mines' ceilings in some places, sparks are occasionally seen, and even some prisoners can be heard screaming in pain as they are tortured; in at least some instances, what sounds like a female's scream can be heard, suggesting that none of the guards discriminate prisoners based on gender. However, new laws have been put in place by the Irken imperial senate condemning harsh treatment of prisoners who are mistakenly sent to Rura Maxis and treated like personal slaves; the harsh treatment is in recent times only for the most hardened and evil of male and female criminals, such as assassins of political heads of state and high traitors to planets. In the past, some levels of the mines were male-only. Some prisoners wear clothing made of the furs of known intergalactic animals, such as the Wolf-boar of Irk and the Bantha of Tatooine. The furs absorbed the heat from the underground mines without making the wearer uncomfortable.
The mines are revealed to be "as big as some planets" and have at least ten-thousand countable levels. Mining was accomplished using pick-axes and what appear to be lasers on the upper levels.
Established sometime prior to the mid-3rd century AD of Earth time, the Irken gulag of Rura Maxis was a prison with no stockade or guard tower or electrified frontier. Its only form of nearby protection was a magnetic shield surrounding the inhabited trilenium mines to prevent unauthorized beamouts.
The stipulations for the inmates of the prison included the simple fact that no one can escape from below. If prisoners worked well, they would be treated well, with good food, a warm place to stay and even have great places to hang out; if they worked badly or behaved inappropriately, only the most hardened of inmates would be exiled to the planet's frozen surface, where nothing could survive for very long without proper weather gear and food.
Some Irken criminals recently convicted of high treason by Tallest ZIM and his queen were sentenced to Rura Maxis to spend the rest their natural lives mining trilenium.
Congregation of Aliens
The "Congregation of Aliens" was a group of prisoners at the Rura Maxis gulag in the age of Tallest ZIM.
When Meedge and Frax arrived at the prison, after having been accused of treason by the High Court of Irk, a large, threatening inmate demanded their allegiance to the Congregation of Aliens, a condition to which Frax swiftly agreed, recognizing that he was not being given a choice in the matter. (Meedge and Frax were subsequently banished to the mines by Tallest ZIM and Queen Gazlene for the crime of treason committed under their service to one of Irk's enemies.)