New answers tagged lost
In addition to sanpaco's answer the reason why The Man in Black can go to the Hydra Island is because that island is essentially part of The Island as both islands are moving together through space and time. This means that he in fact never leaved The Island when going to Hydra and didn't break the rule.
This answer will contain many spoilers if you haven't seen the entire show. First you must understand who/what the smoke monster is. from Lostpedia: The Man in Black was a centuries-old inhabitant of the Island. He was once a normal man with dark hair and steely eyes, but an encounter with the Heart of the Island, brought on by his brother Jacob, ...
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