It can be enjoyed casually solo or with close family like a girlfriend or teenage kids. But with friends you need to schedule long sessions because it’s a huge game. It has 3 difficulties: explorer, balanced and tactician. So a solo explorer play through could be done casually in 30 minute chunks. You might have to pause mid combat during longer fights but it has quick save so you can finish it later.
I don’t know if anyone is interested but there would be more versions too. Solid oxygen (red oxygen) at high pressure used to be thought of as O4, tetraoxygen aka oxozone. But if you look at it with x-ray crystallography it’s O8, octaoxygen. Cool huh