This game is great! A way more fleshed out and well put opus than whichever 2nd Mario Bros. you played before. The difficulty level rises just perfectly, the last world is a good pain in the arse (in the good way), and a whole new pletora of enemies, gimmicks, first debut of the Koopalings, very different levels with the Sun, the underground waters, the puzzles, pipes...

The "main" big problem would be that even if you do get a minimap (for the first time!) there's no instant replayability of the levels, you have to restart from zero if you want it. Aaaand also that holy shit the ending goes by quickly. A quick speech text of Princess Peach tricking you by saying "sorry our princess is in another castle... Just Kidding! ahah. Bye bye" and then it cuts to a very small credits and back to the menu. But still, a good game.

For a mod of NSMBW, dang this game kicks ass! The attention to detail and the meticulous game design makes it very genuine and a very fun game in the end!
Like, this mod has a whole new map that looks magnificient all together, a TON of new textures, enemy retexture, new level themes (like a whole world being in a forest in autumn, another being IN SPACE, WITH THE LOW GRAVITY, HOW COOL IS THAT?!?!), addition of Shy guys all together with ballon shy guys, jumpy shy guys, and more, new unique boss fights that are a bit more difficult to win than in the original game (and then there's the koopalings, which are a joke to beat), new mechanics in each level (like giant pipes, the hammer powerup to beat boos, a train level with gaz smoke that kills you, and so so so so SO much more
There's fricking over 400+ star coins to get!!
And also Lakitu owns a shop now.
AND ALSO MUSIC REMIXES FROM OTHER GAMES!!!
and also new yoshi recolors.

The only BIG default with this mod is that the difficulty is... nonexistent for most of the game (you would lose some lives, but you're really always gonna have ~95 lives on you most of the time) and then comes the 7th world and... Giant difficulty spike.
I swear, I might have lost like a good chunk of lives on one specific level in World 7, then comes the 8th world and it goes back to low. Even the bonus and secret worlds are going without a big hard block!
And also some of the music used is... passable. Some of them are really feeling it's a mod. The boss fight music, or one for main levels (which I think is a remix of World 6th map music in the original game) are really off.

Nevertheless, god DANG it's a good game.