There was peace and harmony that all changed when the three nations water tribes fire nation and the earth kingdom the air nomads stayed out of the declared war the four avatars from the four nations could only keep the balance but, they all vanished the waterbending avatar her brother betrayed her and her friends. 100 years later they were found in an iceberg by an air nomad she recognized one them his was aang, his friends katara, toph bei fong and, zuko. the girl nun of the air nomads she called her hybrid companion when they arrived at the southern air temple azula ( not zuko sister ) was banished she had been she searching for the 4 avatars she could never find them she had to in order to restore her honor. she tried very hard but, had failed every time this she had to her uncle azulon not the old fire lord who passed away before his son and friend of avatar roku. life was different the avatars they had mastered their base elements so the taught each other the opposite element which was tough but, they did it they had to wait for the solar eclipse it gave the avatars ultimate firebending except lose their fire the avatars don't weird huh? next thing they needed to master the avatar state they did here it get's freaky toph and aang are in love and so here katara and zuko they all promised that the would defeat the the nation leaders the power that they have is incredible strength. the banished princess did not know that she was a tri-bender someone who can bend the elements fire earth and air also not knowing that she would join the to end this 100 year war once and for all. the four avatars also learn how take away someone bending ENERGY BENDINGcool right some else learns it too we all know else learns it. the day of the avatar's comet gives those who can bend more than one element which gives the hero's the advantage that ends the and at age 122 they are practically immortal literally katara and her boyfriend get married on the day their friends big (not child birth) day so it became a double wedding the have kids they are mini versions of the parents the kids can bend all four elements the kids are prodigies seriously!