The game had me from the first trailer: A fresh new look for 2D Mario since New Super Mario Bros. (DS) and new weird level gimmicks. I thought the game appeared to have a chill aesthetic with a wacky hidden nature, and that greatly appealed to me.
Each level would have its own gimmick, and if it reused something from a previous level, then it usually would use it in a new fresh way. I can't think of any level that I actively disliked. This game felt like it was littered with way more enemy types than most mario games, so I got to learn all sorts of new ways to approach enemies. Honestly it felt super exciting getting to each new level. I feel like the level designers took a little from Kirby's book, because that's usually what comes to mind when I see levels that use gimmicks to such effective use.
I took my time with this game, starting it early and playing a few levels between other games. I played as Mario the whole time because... Well I have no real excuse. I think internally I try to envision me on the adventure as a character: Usually Mario. 2D Mario usually doesn't "grip" me though. No super exciting story, no big stakes besides "That wacky Bowser is at it again". This game though felt like it really wanted to go more for the Super Mario World feel, where you really felt like you were going from biome to biome in this new kingdom. They have very similar feels to previous Mario biomes, nothing incredibly creative, but there are some swerves here and there as well as some smaller stories involved in locations. There's a whole island of golden waterfalls where a great master "trains" you as you go level by level. There's a mushroom mine where you have to save trapped miners. Even in less creative areas, like the obligatory Magma biome, you see good ol' BJ took over the palace and now the dangerous climate is setting the palace on fire. It's fun to see the Flower People (the toad stand-ins) reacting to the havoc Bowser and his son are causing to the kingdom. It even includes the little epilogues after you save the palaces similar to Super Mario World.
The badges... The badges! I... didn't experiment with them too much. I felt like most of them either would make the game a little too easy for me or just wouldn't fit right in a level not designed for them. I think I might go back and try more of them in the future with regular levels when playing Coop with friends, but for the sake of the review, I will say that most (besides one) were extremely fun to play with and the badge levels designed around them were a fun change of pace from regular game design.
I did not try the online features. I uh... felt like those too would remove from some of the challenge. Again, maybe in the future I'll try them out. They seem great for kids to help their friends through levels and see what their friends to to beat difficult levels.
I think the only disappointing thing in this game is the final boss. It felt a little... anticlimactic after all the build up throughout the game, though it was still fun. No spoilers here, but don't expect as grand of a finale as the big turtle promises.
To end my rambling, I've never talked about a 2D Mario this much before. A fantastic comeback for Mario in 2D. This is the 2nd 2D Mario game I've 100%'d I believe (the first being NSMB DS), and there's good reason for that. Very solid gameplay as per mario's usual, very creative levels that feel new and unique all the way through, fun and creative enemy designs, a beautiful art style, a cute story that follows with each new area, and honestly I want the team to keep up the amazing work. I think this was the first time I was extremely excited to pick up a new 2D Mario game on release since I was a child, and I was not disappointed. You aren't getting a nail-biting epic, but you are getting a fun adventure that you can come back to as often as you want and it'll surely bring a smile to your face each time.

Perfected the Donkey Kong Country formula. Felt like the level themes were too samey or few in DKC1? This game has a ton more variety on Crocodile Isle. Bosses are more than "Jump on it" and more numerous. Diddy and Dixie are both light and have a quicker pace than Donkey. Dixie's hover will feel like a nice breeze to get to difficult jumps when you're struggling. The graphics are still beautiful and go nicer with the more varied stage themes. The music... I'd buy it on vinyl if I could. 102% completion is very possible without a guide, as the levels do much better at throwing you little clues around, and far less cryptic than DKC1. Game just feels satisfying to play. One of my favorite games of all time and deserves every little bit of praise I can give.