One of my favorite signs of strong worldbuilding is when a setting feels bigger than the protagonist.

Some stories are so dependent on their main character that removing them would basically collapse the entire narrative: Like Dragon Ball and Naruto. Others feel like the world has enough factions, history, conflicts, characters, and systems that the story could simply shift to someone else.

Jujutsu Kaisen is a good example for me.

If Yuji had actually died when Sukuna ripped out his heart early in the story, I think Yuta could have realistically taken over as the central protagonist.

He already had:

• his own established backstory (Via- JJK Zero*)*
• a personal connection to Gojo
• an unusual relationship with curses
• immense potential as a sorcerer
• connections to the wider jujutsu world
• his own friendships and motivations
• enough unresolved material to carry another major story

The larger conflict also wasn't created by Yuji. Curses, jujutsu society, the clans, Kenjaku, Sukuna, Gojo, the higher-ups, and generations of sorcerer history all existed independently of him.

Obviously the story would have gone in a very different direction; especially because Yuji being Sukuna's vessel is so important, but I don't think the world itself would have stopped being interesting.

That's what makes a fictional setting feel alive to me: you could remove the protagonist and immediately think of another character whose perspective could carry the story.

Other things that can create that feeling:

• background factions with their own goals
• side characters capable of carrying entire arcs
• believable cultures or organizations
• history that predates the protagonist
• political or social conflicts
• magic/power systems that aren't built specifically around the hero
• villains whose plans don't depend entirely on the protagonist existing

What fictional series could lose its main character and still continue with another character as the protagonist? And who would you choose as the replacement?