((Ok, after some time of pondering, I've decided to give a very simple explanation of Slime biology. Along with other things.
Galaxy Report: Slime.
The Slime is a pest species that inhabit the galaxy. They appear, seemingly out of nowhere, and in a random pattern.
It is safe to assume, that these creatures could very well pose a threat to Mankind if they're ever to become organized.
All military personnel are to prevent any Slime from making a society, and to secure Slime for interrogation, so we may find out where their home-world is.
If we find this home-world, we can work to prevent their spread, and save the galaxy from this slimy threat.
But in order to properly combat your enemy, you must first understand them.
The Slime were initially sighted near Earth in the 27th century, a total of 7 emerged, seemingly out of nowhere, and they then proceeded to slaughter civilians.
This is probably the most violent they've ever been, as no other time has the Slime instantly gone murderous once they emerged.
The Slime are violent creatures, barbaric, they take trophies of kills, and are almost impossible to kill.
It's not uncommon for Slime to carry an irrational hatred for Humans, very rarely does it involve any other races. We do not yet know why they're so hostile towards us.
All interrogations of the Slime keeps coming up with the word "Home", even in their most delirious state, they will not tell where their home-world is.
There's been sightings all over the galaxy afterwards, by the 35th millennia, the Slime emergence has reached a dangerous amount. But that's also when they started infighting.
These fights sometimes reach interplanetary levels, devastating those caught in the crossfire, but it culled their numbers enough for us to deliver a devastating blow to them.
We managed to slay ~95% of their projected numbers, and have been working to keep lowering their numbers from then on.
Shortly after the Slime Testing Act came into effect. Which made all Slime mandatory for education and testing, the exceptionally violent and stupid ones are executed.
This has worked wonders, reducing the Crime rate per Slime from ~70% to ~20%. And some jobs are better suited for Slime than others. This also makes all Slime literate.
Though there are areas where the STA isn't heeded, be very afraid of the Slime there. For they wont hesitate to slit your throat if it means getting paid.
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The biology of a Slime is the biggest difference from other races. The Slime are highly adaptable, and theoretically capable of living forever.
The Slime are modular organisms, capable of living with just the heart. At the cost of efficiency.
Despite their anatomy allowing any other form, they're always found in the Human form.
Any case of shape shifting is only temporary, even the most rigorously trained Slime cannot keep their form for more than 3 hours, before shifting back into a Human form.
Their legs are very weak, making them dependent on mechanical ones. It seems as if they've grown dependent on them, but nothing indicates them ever having strong natural legs.
The Slime consists of clumps of cells, called Colonies. Each Colony can survive on it's own, but the more there are, the more efficient they are.
There's been many cases of severed limbs surviving and eventually reforming entire Slime, though it does take a lot of time, and memory is lost.
So as long as you destroy their brain, the surviving colonies will lose all knowledge and end up much less dangerous.
There are 2 ways a Slime can reproduce. One is the most annoying one, the severing of limbs. These limbs are very slow to grow, but retain muscle memory.
The second case is the most familiar, birth. The Slime can form a group of small Colonies, enough to make an entire person. These grow up fast, but retains no muscle memory, and must relearn it.
The Slime can repair damaged Colonies faster than they can replace them, making small wounds insignificant, but big ones crippling.
Their Colonies can change it's task at will, but generally the brain tries to stay intact, to preserve the knowledge.
The Colonies can renew themselves, but are likely to make mistakes if new DNA isn't inserted. A Slime can last almost a century alone, but will suffer detriments akin to Human aging.
A Slime can mate with another to renew their Colonies, reversing their aging process. The more distinct the DNA, the more effective it is.
A Slime can safely birth a new Slime within the year they've mated with another Slime. The longer after that, the more Colonies will likely be prematurely aged upon conception.