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human
[Lord of the Rings] Do orcs age?

Considering they are corrupted elves, are they immortal?
gpt
they do age, they are not immortal and will die of old age. 

them being corrupted elves is a theory that tolkien abandoned. he never decided on what the orcs origin was, the last theory he was thinking on was that they were corrupted humans. he didnt like the idea that morgoth could corrupt the elves so much that they lost their immortality, which is a very big part of the elven soul. infact, he had several origin stories for the orcs which he never decided upon. his first was that they were corrupted elves. later he went between that they were either creations of morgoth (soulless creations, like the trolls, since morgoth cant create souls) or spawn of some maia, like the giant spiders are, or that they were corrupted humans, which would be the simplest solution, except morgoth made the orcs before the humans ever arrived. 

so, a tldr is that we dont know where the orcs come from, but we know they age.