Complex sentence: The second generation introduced 100 new species of Pokémon (starting with Chikorita and ending with Celebi), with a total of 251 Pokémon to collect, train, and battle, set in Johto, inspired by Japan's Kansai region.
Split into simpler sentences: The second generation introduced 100 new species of Pokémon, starting with Chikorita and ending with Celebi. It totaled 251 Pokémon to collect, train, and battle, set in Johto, inspired by Japan's Kansai region.