system
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human
How do orcs work in Lord of The Rings?

Uruk-hai are dead elves, but are all orcs just dead things from various species? Shouldn't we see dwarf orcs ect.?
gpt
Uruk-hai aren't dead anything - their origins are hidden but it's probable that they are hybrids of orcs and men bred by Saruman - their man-blood is what allows them to stand daylight.

Orcs are elves that were corrupted by Morgoth thousands of years ago - how they *go on* reproducing isn't known, though it almost certainly doesn't involve corrupting *more* elves, there just aren't enough left to account for the vast number of orcs/goblins in existence. It's possible that there are no 'other species' orcs because none of them inspired the same jealousy in Morgoth that the creation of the elves did, and he didn't feel the need to work with 'lesser' stock.

(These are the most commonly 'accepted' explanations, though neither is absolutely word-of-god endorsed because it's often not specified, for example, it's never made exactly plain that the man-orcs referred to in the book *are* Uruks, but it's a fair assumption).