https://www.gamespot.com/articles/pokemon-ultra-sun-and-ultra-moon-the-definitive-3d/1100-6455086/

Last year’s Pokémon Sun and Moon celebrated 20 years of Pokémon games with new creatures, a new structure that did away with gym battles, and lots of interesting twists in Pokémon’s increasingly rich lore. Long-term Pokémon fans and newcomers alike loved catching ‘em across the Alola region, and the games proved that there was still plenty of life left in the 3DS.

Ultra Sun and Ultra Moon take things even further, with brand new story elements, characters, areas, Z-Moves, and general improvements across the board. They build on the original Sun and Moon, offering new challenges and twists that fans have never seen before. It’s the ultimate Pokémon experience, whether you’re a seasoned veteran who has played every previous game or a newcomer who has tried Pokémon Go and wants to try the full Pokémon experience!