This game is amazing but I just want to put it out there that it lacks in a wider story. You get all these kingdoms to explore and while there is some narrative there isn't much past your initial visit. There's so many moons and most are repetitive which is fine but less fine when you consider some of those moons are shop moons that cost 1000 coins for all of them in each kindgom. That and you can just blow through the game so fast which is also ok but again made less okay by the fact that most 3D Mario titles like Galaxy 1 and 2 and Sunshine all had super in depth stories with some extra stars hidden here and there. Odyssey doesn't even require you to collect all of the story moons for you to complete the game.
Now with that said, go buy the game it is amazing and has so much to offer even if it is just so spread out and non-linked.