This game is about as close to perfect as you can get.
Super Mario World also throws in some new and interesting elements of gameplay. For example, there are essentially four different types of stages: regular, castle/fortress, ghost house, and switch palace. That's without even making the distinction between normal and secret stages, or between castles and fortresses. The eight castle bosses are fought in five different ways, and even the ones that are the same, such as Morton and Roy, have one element of the fight changes that makes it slightly different. At several points during the game, you will have the opportunity to warp to "Star World", which is basically World 8 of the game, a mystical world up in the sky. From there, you can go to the Special World, World 9, which houses some of the strangest, most interesting, and most difficult stages in the game. You can even take shortcuts and/or alternate routes in several places. This game also introduces Yoshi (in four different colors!) and the magic cape, which allows Mario to perform some impressive aerial stunts. Chocolate Island 2 also has a special quirk about it that makes for a unique style of gameplay.
With everything considered, Super Mario World is just a very awesome game. It's not only the kind of game that you can play through and find all of the secrets, it's the kind of game you can play again and again. The one thing that knocks two decimal points off it and stops me from rating it a perfect 10 is the fact that there is little variety in the the environment, at least as far as different enemies and hazards (and music) are concerned. The enemies and obstacles that appear in an icy stage are no different than those in a grassy or cloudy one, although some underground enemies do seem to be unique to that environment. The music is also based off the exact same theme in every stage, though with variation depending on the environment. (It is kind of interesting how they did that, but even so…) Of course, I'm not about to let this minor defect stop me from enjoying this game. To everybody reading: If you have a Super Nintendo but don't have this game, get it, even if you have to look through every secondhand video game store, garage sale, and eBay page from here to Indonesia.