First of all, the story of Pokémon Black Version is one of the best in the entire series, with unique characters and the best evil team with a kick-ass battle theme.
Furthermore, this is the first Pokémon game with constant animations during battles, and they look great. The game looks smooth and runs at a consistent frame rate of 30fps (and even 60fps for battles!). Sometimes you forget that this game is running on a DS Lite!
Also, this is the first Pokémon game where you can use TMs infinitely. This saves a lot of trouble because in the old games, you had to keep going back to the Battle Frontier and grind BP to get the same TM again.
This game also features seasons, where different Pokémon appear depending on the season. The season changes every month, altering the aesthetics. Unfortunately, this feature never returned after Pokémon Black 2 and Pokémon White 2.
Additionally, this is the first Pokémon game with a habitat list of Pokémon, making it easy to track where you have seen all Pokémon.
Lastly, there is a substantial post-game with plenty of things to do (such as the Battle Subway and new locations).
Cons:
The region is linear. By that, I mean that the routes mostly go in one direction, and you just follow a straight path to the next town/city. This makes the landscape seem less beautiful and adventurous compared to, for example, Pokémon Ruby or Pokémon Platinum.
Furthermore, the beginning of the post-game is ridiculous. When you battle the new trainers at the start of the post-game, their Pokémon are 20-25 levels higher.
Lastly, the version-exclusive Pokémon and locations (White Treehollow and Black City) are poorly chosen and not very significant. In White Treehollow, you can get new Pokémon from other regions, but you only reach it towards the end of the game, and the Pokémon are at level 5, which is too late. Black City provides daily trainers to battle, but they give little experience. Moreover, nuggets are sold in a shop there for 3 times the selling price, which is the worst deal I have ever seen in a Pokémon game.
Conclusion:
This game is definitely recommended, even though it may feel linear and dull at times. In my opinion, this game is "the one to rule them all."
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