Orks are a humanoid, green skinned race in the universe of Warhammer 40 000. They are by far the most fun, unusual, and in my humble opinion, the best race in all of SF. There are many reasons why I think that most of them are personal, but I do have them.
Orks were made during the War in Heaven, a cataclysmic war that almost destroyed the entire galaxy. They were created as a weapon to fight against the Necrons and the C'Tan. It was a war where whole solar systems disappeared, whole planets were collateral damage. Current galaxy is ravaged by all consuming war and destruction, but it can be considered a simple skirmish compared to the War in Haven. Ork creators were the Old Ones, nothing is known about them, not even their name.
Orks are a strange combination of animal and fungus. They are very strong and ridiculously difficult to kill. They can keep fighting without an arm, or a leg. They can even survive and fully function after a head transplantation. They do a lot of various cybernetic enhancements, but all of them are very crude and may seem primitive, as is the rest of their technology. All of it looks ramshackle, armor plates slapped on and just painted over. With visible screws and nails all over them. When Orks settle a planet, they bring their entire ecosystem with them. Ork spores produce food, drinks and several Orkish sub-species, Gretchen, Snotlings, and squigs.
Some might see Orks as stupid and unintelligent. It is very easy to think so if you look at them from the distance. They value strength over everything else. The Ork who is bigger is considered better. Their currency is that, that they collect by beating one another. They do not have any education system, no training, or anything like that.
Ork live for fighting, war for them is just a big fight. A s they fight stronger enemies and survive, they become stronger and more powerful. They also become bigger and smarter. This makes Ork hierarchy easy to understand, the bigger the Ork is more important they are.
If left alone for a long time, Orks can become immensely powerful. Enough to threaten the entire galaxy. Even whole Space Marine legions were having difficulty facing them. In one of those fights, the Emperor himself had to step in in order to win the war.
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