Millions of years ago they were trapped underground by a massive comet impact which decimated the surface of the planet. This was many millions of years before hominids evolved. Before the impact they were a civilized, peaceful society. After the impact, volcanoes erupted, earthquakes shook the planet to its core, and a massive global firestorm scorched the surface. Clouds of dust and ash blocked out the sun. Nuclear winter set in turning the planet into a giant ball of ice. Deep beneath the surface however, life evolved.

The Terrians, as they were known in ancient times, moved underground to survive the deadly cold. They burrowed deep into the earth where they found warmth closer to the mantle and there they thrived. Their ancestors had the foresight to bring seed and grain and livestock into vast underground chambers during the beginning of the Great Winter.

Water was plentiful. The deeper they dug the warmer it got. At a point deep beneath the surface the ambient temperature of rock becomes warmer than the surface. Heat radiating from the mantle keeps it warm enough for life to survive. The mantle is a thick subterranean ocean of semi-molten rock surrounding the planet’s core. Get close enough to it, or an underground lava chamber and you can survive down there. Not too close though, because it’ll cook you alive.

After the asteroid impacted the planet, it set off a series of cataclysmic natural disasters that devastated the the surface. Eventually the volcanoes stopped erupting and the planet cooled from the vast clouds of dust and ash in the atmosphere. This forced the Terrians deep underground in an effort to survive. Fortunately their ancestors had the foresight to prepare for just such an event.

Their ancient culture centered around astronomy and science. They discovered a comet headed for their planet and they prepared themselves for the inevitability of the impact. The comet was over 100 kilometers wide and came from the outer solar system, most probably pushed into the inner system by a neighboring star as it passed close enough by for it’s gravity to affect the cometary cloud surrounding the star system.

So they prepared. They didn’t have the technology to deflect the comet, or to blow it up, and that could have possibly posed an even larger threat. However, this caused conflict within the populace. One group of Terrians didn’t agree with the scientists and wanted to launch all their weapons at the comet to destroy it and wouldn’t listen to anyone who tried to tell them it wasn’t possible. They had hundreds of years before the comet would impact, surely they could develop some kind of technology to destroy or deflect it in that time. So they tried.

Conflict grew and no one could agree on the best solution. This was the beginning of the end of their united society. Over time the divide grew. There were many groups and camps of thought, some believing one thing others believing another. Some of the religious began to believe it was all a hoax propagated by the ‘evil greedy mad scientists who wanted all the wealth and power’. The division grew.

Meanwhile the comet continued on it’s nihilistic path of destruction headed directly for the planet. The extinction of the species, the end of the world was coming, and no one could agree on how best to handle it. Some groups tried raising the capital to build ships to escape the planet, but still others who thought science was a conspiracy to destroy their gods sabotaged the efforts and destroyed many ships.

Tensions grew, resentment and mistrust forced increased security and secrecy. This increases the lack of trust. Some grew paranoid of everything the scientists or government did. No one could tell who was telling the truth. No one trusted anyone. People fought. War broke out.

A group of scientists and intellectuals secretly moved their work underground and continued to stockpile seed and grain and build vast caverns and lakes miles beneath the surface. They had many vaults scattered around the planet, all with redundancies of every known seed and grain known to their science. They built vast vaults filled with frozen embryos of every animal they could find. They did this for hundreds of years. Growing food, building a massive system of underground tunnels and caverns.

They also built more starships; more like rudimentary rockets, really. However the conflicts, skirmishes and terrorism from fringe religious groups kept up their attacks. War prevented the building of the ships to escape the planet. The pointless idiotic war continued. As soon as one terrorist group was destroyed another popped up to take its place. These groups were cult-like religious, anti-science zealots who wanted nothing more than to destroy all vestiges of the people they deemed evil. The ones they believed were trying to destroy their gods and their beliefs. The irony of their ultimate destruction by the comet was lost on them right up until the moment of impact when the firestorms came. A wall of fire raced around the planet at hundreds of miles per hour, scorching the surface and destroying everything in its wake.

Those not killed in the initial impact nearest ground zero were killed by the concussive blast equal to millions of nuclear bomb detonating at once. It shook the whole planet and caused earthquakes, tsunamis, and massive volcanic eruptions.

This day was known as the Great Destruction. An extinction level event that forever changes the evolutionary path of the Terrians.

Underground, oxygen is produced by underground agricultural facilities which pumps fresh air through the natural lava tubes and up into the larger now-empty magma chambers which once held billions of cubic meters of lava.

Terraculture became the Terrians savior and allowed them to thrive underground for millions of years. But of course, the Terrians were not alone. They called these creatures Gaugs.

The Gaugs are violent and horrifically hideous creatures that prey on each other and other Terrians. Legend has it that the Gaugs are former Terrians that split off from the main survivors of the Great Destruction millions of years before and evolved into what they are now. But most don’t believe this story and dismiss it as legend and myth told in the years immediately after the Great Destruction. Regardless of whether it’s true or not, the Gaugs exist and they pose a great danger to the Terrrians. Some tried to go back up to the surface but died from the cold which could get down to -150 degrees celsius.

Gaugs are fierce and deadly. Their skin is thick and rough, pale and scarred from a lifetime of countless fighting. The older males are venomous. The venom is a fast acting neurotoxin that paralyzes its prey -usually a Terrian- within a few minutes. Gaugs are terribly strong, which aside from their venom, makes them extremely dangerous. They see in the dark, have a single large and dark oval-shaped eye under a jutting and thick brow ridge and no nose to speak of other than two small vertical parallel slits above their teeth filled mouths. Their main front teeth, two pairs -upper and lower- were sharp and form two semi triangular elongated sets. Honed from millions of years of evolution. The back teeth, dull and worn, for grinding and crushing their main food source, the Terrians. Their jaws are so powerful they can crush rock. A fact of life when you live underground clawing and chewing your way through the subterranean world. Their short powerful five-fingered claws, sharp and deadly. Their bodies are short and stout, muscular, bipedal with massive thighs, calves and short almost hoof-like feet with 3 large short hoof-toes, each with a large thick nail wide enough to give good traction on rock and gravel, but sharp enough to rip flesh from bone. Gaugs can walk upright but are better crawlers and leapers than anything. They run on all fours, much faster than a bipedal hominid. They are very sensitive to the cold, and this is one of their biggest weaknesses. They’re extremely hard to kill with traditional weapons and when they attack they attack in packs like wolves. They’re relatively smart and they have basic tool making ability. Rumor has it they have a rudimentary language, perhaps leftover from when they were Terrians, if that legend is true.

They are a cannibalistic species, and tend to gang up on the larger males of their kind. They kill and eat each when their main food source is unavailable. Which was usually when the Terrians would push them back down into their dens. Gaugs live far beneath the Terrians, closer to the mantle in places so hot it would be enough to cook someone alive.

It is an ongoing conflict between the two groups. Almost a daily problem. No one knows how many Gaugs exist because no one wants to go down there and find out.

The Terrian cities are connected by a maze of tunnels, roads, thousands of miles of tunnel roads, vast chambers and rooms. Large buildings built into the walls of huge caverns. Housing, farms, schools, all guarded and secured from Gaugs by massive steel doors built into the rock.
There are pools and ponds and a lakes as well. Plenty of water to drink. They have everything they need.

The planet is still frozen. They cannot leave. They’re trapped underground with the Gaugs. The life of the Terrians is simple. Survive.

Only now, the Gaugs have a surprise for them.