The moral could be about the consequences of excessive scientific experimentation. In Old World Blues, the scientists' over - ambition led to many problems and mutations. It shows that when we play with nature too much without proper ethics, chaos can ensue.
The story of Fallout New Vegas: Old World Blues is about the Courier getting involved with the scientists in the Big MT. They are these eccentric and somewhat mad scientists who have been conducting various strange experiments. There are a lot of unique characters and creatures there, and the Courier has to navigate through their wacky plans and power struggles while also dealing with the technological and moral implications of the science going on in that area.
Through the characters. For example, the mad scientists in the game represent the consequences of unethical scientific pursuits. Their actions and the resulting chaos are a clear sign of what not to do, which helps convey the moral.
The 'old world blues story' is often about the reminiscences, perhaps the sorrows and joys of the old world. It could be about historical events, cultural traditions, or the lives of people in the past.
It could be the musicians who were part of creating and spreading the blues music in the old world. They are the main characters as they are the ones who pour their emotions and experiences into the music.
Rito Hoi was a Japanese mangaka who was famous for creating romantic, adventure, fantasy and other types of manga. His unique style of work was deeply loved by Japanese anime lovers. His representative works included Vampire Hunter D and Chronicles of Wings.
One funny HoI4 story is when I was playing as Italy. I decided to invade a small nation just for the fun of it. I sent my troops, which were a bit of a ragtag bunch at the start. But through some lucky battles and a lot of bluffing with my military postures, the small nation surrendered without much of a fight. It was hilarious how my half - prepared army managed to scare them into submission.
Well, it could be about the history and the secrets hidden within the old city. The 'blues' part might imply a sense of melancholy or the hardships faced by the people there. It might also involve some kind of mystery or adventure that unfolds in the alleys and old buildings of the city.
I don't know for sure since I haven't read it. But they could be typical characters like a detective trying to solve a crime in the old city, or a local artist who is inspired by the city's charm yet also frustrated by its problems.