The Legend of the Westen Water Tribe

Water. Earth. Fire. Air.
Long ago, the four nations lived together in harmony.
Then everything changed when the Water Tribe attacked.

Only the Avatar, master of all four elements, could stop them. But when the world needed him most, he vanished.
A hundred years passed, and the Water Tribe continued their relentless conquest. Their powerful waterbenders, with their mastery over ice and the sea, devastated the lands, flooding cities, and freezing entire armies in their path. The Earth Kingdom, though strong and enduring, struggled to resist the unending onslaught of the Water Tribe's forces.

Some people believe that the Avatar was lost forever, taken by the tides of time.
But I believe the Avatar will return to save the world.

1000 years after Avatar Aang era.