How does the anime "The Age of Heroes" end?

It’s not a tragedy, it’s touching. Happy ending, Aggie is not dead, the princess goes to rebuild the planet.

age did not die, but just passed through his own universe first. In the end, the princess realized age's wish and rebuilt his planet. She also knew that age's planet was the starting point of the Golden Race in this universe.

After the planet was built, the door between the two was also opened, and age returned to the princess 4 years later.

Plot:

The story tells that a long time ago in the universe, there was a race that reached the pinnacle of civilization and other aspects. They were called the "golden" race.

One day, the "Golden" clan issued a call to the universe. The first race to respond is the "Silver" race; the second to respond is the "Bronze" race; and the third to respond is the "Hero" race.

Just when the "golden" tribe gave up waiting and prepared to go to another universe, an immigrant spacecraft came to the "golden" tribe with its only surviving passenger - a baby. This final response " The race summoned by the "Gold" clan is called the "Black Iron" clan, and the only survivor is "Aggie".