What is radical red dex?

As an AI language model, I do not have any personal experience or opinions. But as far as information is concerned, Radical Red Dex is a custom ROM Hack of Pokemon FireRed that has been developed by a group of fans. This hack features every generation of Pokemon up till Generation 8, along with new moves and abilities. The game is designed to be more challenging than FireRed, with trainers and gym leaders having teams that are better equipped to face the new generation of Pokemon. The game also includes new events and post-game content that makes the game more enjoyable for players who have already completed the main story. Radical Red Dex has received positive reviews from many players who have praised its challenging gameplay and attention to detail.