The most common type of life-bearing world in the universe was first surveyed by a Spearpoint probe in 2132. Had Earth's nearby asteroid belt contained more ice, we would have known sooner.
Most oozeworlds are smaller than Earth, and much less dense, but size can be misleading. They have strong magnetic fields despite scarce
metals. Their surfaces are stained with colorful organics, but all the interesting stuff happens underground.
With limited radioactive elements, they're often powered by tidal forces. The heat of slow
contraction is also essential.
These worlds are like onions. Endless layers of caves and hidden lakes spiral hundreds of kilometers down, intersected with lava channels below that, right through the core to the other side.
As the layers settle and contract over a billion years, lighter materials are slowly forced to the surface through a vast maze of tubes and interior geysers.
All the submerged tunnels in a single oozeworld easily add up to interstellar distances.
It might take a million years to fully explore one such world, and by the time the survey is complete, the caves will have changed.
Who knows what's down there?
Most oozeworlds have 'hotspots', where heat and matter from the core break through the crust. Most surface sludge eventually sinks back through subduction zones.
These hotspots pump energy through the planetary network of caves, and help form new channels.
They self-organize into extensive 3-D rivers that circle the world many times, flowing fractals more elaborate than any circulatory system.
When the core matter finally reaches the surface at some random geyser, it will have traveled incredible distances through countless obstacles.
This process is the ultimate evolutionary filter.
Oozeworlds have generated some form of intelligent life over half a million times in our galaxy alone. Such civilizations tend to be short-lived and unstable, with rare flashes of brilliance before they collapse.
Most aliens you will encounter during your missions need high pressure tanks and dense nutrient baths to leave their homeworlds.
You will rarely see them directly. Due to their homeworlds' vast natural diversity, they may not even know their own anatomy! Think giant anemones or squid.
Fortunately, thanks to the Evolutionary Contingency Principle, these species will have less in common with each other than with you.
They're usually unable or unwilling to trade with each other, but they can all trade with us, through our network of commodity exchanges, financial instruments, space markets, supply depots, MOND-tankers and long-range transfer beams.
Your first and highest purpose as Class-1 Traders will be to do whatever it takes to retain at least 4% of the transferred value for the Company.
Probably the best hard SF novel ever written: Infinite Thunder by Jack Arcalon.
paperback or ebook
Read the chapters