Although Generation IV is the successor to Generation III, it is not a direct sequel. The Hoenn region is inaccessible in all Generation IV games. All three Generation IV games are concentrated in the Sinnoh region and remain compatible with Generation III games. Generation IV introduces new Pokemon that are directly related to previous versions in the earlier three generations.
• Generation IV introduced 107 new Pokemon, bringing the total number to 493.
• 113 new moves have been introduced, bringing the total to 467.
• 47 new Abilities have been added, bringing the total to 123.
• Four new boxes have been added to the Pokemon Storage System, bringing the total to 18.