Generation III/Advances in Gameplay/Major Alterations from Generation II


 * A complete overhaul of the Pokémon data structure; Pokémon now have an individual personality value which can range up to a number above four billion. Abilities and natures, also newly introduced, are determined based on this value, as is a Pokémon's gender, while the system has been overhauled for greater variance (0-31 rather than 0-15 as it was before).  is now based on a calculation between the personality value and Original Trainer's Trainer ID number and secret ID number with the same rarity.
 * An overhaul of the Berry system introduced in Generation II: old Berries rejected in favor of Berries which grow individually as plants and can be picked and planted elsewhere. The Berries are now named after real life fruits instead of their "basic" names from the previous generation. The effects of the first ten new Berries are similar to the ten Generation II Berries.
 * Each Pokémon has its own status screen sprite, for ease of use in the party screen or PC.
 * The function of the built-in clock was greatly reduced. There are no cosmetic changes during different times of day and Pokémon appearances are not affected by time. Also, the day of the week is no longer tracked.
 * have no built-in clock at all.
 * The seven Poké Balls made from Apricorns, along with Apricorns themselves, are unavailable in Generation III.
 * In battle, passive damage (such as from, and ) is now resolved at the end of a turn, rather than immediately after a Pokémon attacks. In previous generations, such damage did not occur after a Pokémon, that would have taken passive damage, knocked out another Pokémon.