Hoenn is the region introduced in Pokémon Ruby, Sapphire, and Emerald.
The Hoenn region debuted with Pokémon Ruby and Pokémon Sapphire for the Game Boy Advance in Japan in 2002, followed by Pokémon Emerald in 2004. The setting contains towns, routes, caves, oceans, and islands, placing a stronger emphasis on water travel than many earlier regions.
Ruby and Sapphire introduced the third generation of Pokémon, adding 135 new species and raising the National Pokédex total from 251 to 386. The games also introduced abilities, natures, double battles, Pokémon Contests, and weather effects as major gameplay features.
Hoenn is associated with the legendary Pokémon Groudon, Kyogre, and Rayquaza. Team Magma and Team Aqua serve as the main villainous groups, with their competing environmental goals driving the central conflict. Hoenn should not be confused with Johto, which debuted in Pokémon Gold and Silver, or Sinnoh, which arrived later in Pokémon Diamond and Pearl.