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Can we get a Legendary theories/autism thread?
It's obvious not all of them are "forces of nature" or "god-like beings". Multiples of certain species apparently exist, Latias' dex entry straight says they travel in herds for example. Some of them are just exceedingly rare for one reason or another so they became "legendary".
As for breeding, lots of animals refuse to breed in captivity, so that may have something to do with it. Plus the lines have been blurred with the additions of Manaphy, Cosmog's forms, and UBs.
For example:
>Heatran can be either gender, so they certainly aren't unique.
>They are probably only "legendary" because they all live below the earth's crust and rarely come topside.
>If they all normally live down there, it'd stand to reason they'd want to breed there as well. The heat and pressure may play a role in reproduction.