Termina is the setting for the game, The Legend of Zelda: Majora's Mask rather than Hyrule. Some people think Termina is another country while others think it is some sort of alternate universe, due to the strange way Link gets there and the fact that Ocarina of Time were reused so it seemed like everyone had an alternate twin.
Termina was created by the Four Giants. This region is in grave danger from the Moon, and Link has to save the Four Giants from the Swamp, Mountains, Ocean, and Canyon to stop Majora's Mask from destroying Termina.
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