Don't bother with 3 or resurrection though
These are the two films from the series that I've seen, and both were ok, but not great. I've seen snippets of the first two, and they look much better.
Anyway.
*in character voice*
Author: Darthos Cade
To: Sheelan Cade
Rating: Urgent
Sheelan, Biologis Haines has been doing more research in the past month, but has now mysteriously disappeared. The creatures have begun to mount an assault on our base of operations down at the planet's surface.
I've attached some of Haines' research to this message for you.
I must go now. I am needed at the base.
The Emperor Protects
Darthos.
***
File Attached: 24Z-Alpha-AlphaQ
Opening . . .
These creatures are remarkable pioneers of evolution! They are incredibly tough and strong, and move far faster than anything my initial studies could have revealed.
Their claws and teeth appear to be compounds formed from keratin and a naturally formed silicate structure; the silicate forms the core of each tooth or claw and the keratin sheaths it. This means the claws and teeth are extremely hard-wearing and almost unbreakable, and as the keratin sheath is worn down it is quickly regrown to form a razor-sharp edge.
This allows the creatures to form the tunnels and burrows they live in very quickly, and they can dig towards their prey, using their heightened senses to pick up vibrations.
Their ears are long slits located on the side of the ribcage, underneath the armpit. Testing has revealed their hearing to be at least five times more sensitive than that of the average human.
The jaws are powered by muscles with a high number of fast-twitch muscle fibres, allowing them to exert huge forces when biting. I estimate the pressure generated by the bite of one of these creatures to be somewhere in the realms of two thousand pounds per square inch. Evidence on the battlefield supports this; I have seen a man broken in two with a single bite, not to mention the destruction they can cause to ranged weaponry when they get close. Although I have explained numerous times to the storm-troopers that I specialize in bio-mechanics, they still insist on bringing their hell-guns to me for repair. In most cases, the weapon is beyond repair, often having had the barrel or power-ports crushed.
The creatures' teeth are somewhat serrated but also taper to a point, allowing them to grip or cut as required. The teeth are also home to some of the most virulent strains of bacteria I have ever encountered; in many cases, those who are bitten are too ill to continue fighting once their wounds have been treated. I have been forced to perform many amputations and bionic replacements to prevent soldiers from losing their lives to gangrene.
The tentacles are both an extension of the creatures' digestive tracts and the housing for their olfactory and taste organs. The creatures cannot use these tentacles to grip anything, but have a certain amount of control over them, allowing them to position the tentacles to taste and smell a potential food item before ingesting it. These organs are so sensitive that when we lay out corpses stuffed with poison, the creatures ignore them entirely, instead of falling upon the dead flesh and devouring it, as is their usual behaviour towards any dead creatures, and particularly human corpses, left outside the base's walls.
Finally, my autopsies have revealed a fatal weakness in these creatures. When a human is shot in the head, there is a fairly good chance of survival (depending on the weapon used, obviously), as the skull will absorb much of the impact and occasionally deflect or stop the projectile, thus protecting the brain. However, these creatures have only a thin layer of cartilage and their groin muscles protecting their brain, at least from the front. From behind, the pelvic bones provide good protection; but a good shot to the groin from the front will almost always kill these creatures. Even in the cases where the shot misses the brain (which is significantly smaller than a human's), the shock and trauma tend to do enough damage to either kill the beast or knock it unconscious at the very least.
This weakness gives us a chance, at the very least. A chance.