Pokemon Sweltering Sun is VERY different from the average ROM Hack that you might be accustomed to. It has EXTREMELY in depth buffs and changes to EVERY single Gen 1-7 Pokemon, 670+ move changes (with 130+ brand new moves), 20+ custom new abilities, game-changing item buffs and so more to offer. Also, fair warning that this is a long, wordy post. I would just recommend checking out the in-depth documentation linked below. Everything you could ever want to know about the hack is on there. This project is absolutely massive and took a LOT of time to complete and perfect. The best way to see it is to check it out yourself. I’m very detail oriented as you’ll see from the documentation, but it means there is a lot of new stuff and I have trouble summarizing it all.
ANY and ALL Pokemon in this game are HEAVILY and EQUALLY buffed and viable in this game, more than you’ve ever seen before. To those who have not played the game, it may seem like absurd power creep and making “every Pokemon broken.” In a competitive sense, this is 100% true. Not only in the more obvious/eye-catching offensive ways, but all kinds of crazy defensive Pokemon with defensive abilities, buffed Black Sludge and also crazy utility in all sorts of new moves and pre-existing utility moves being much more common and widespread. But if you truly play the game you’ll soon see how the interactions work and that every Pokemon feels like they’re on an even playing field. You aren’t meant to look at the Pokemon changes or move changes in a vacuum, or as if this was a thing in a real Pokemon game with online play. It’s all relative to itself.