When were all the changes to the Special group made in Pokemon History?

Question

I am talking about the special stat group in case you were wondering. Special stat group is sp. atk and sp. def now a days

Comments

I'm sure you know that the Special stat split in Generation II. What else even is there to look for?

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Gen 4 physical/special split?

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Every main series Pokemon game since gen 2 has used the same 6 stats.

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In gen 2 the old special stat was split into special attack and special defence. Then in Gen 4 there was the physical/special split that made it so that the category of a move was no longer determined by its type but rather determined by the move itself. I'm pretty sure those are all of the changes.

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If you know it answer

Answer 1

The Special stat (Japanese: とくしゅのうりょく special ability) is a stat that exists only in Generation I.

The Special stat accounted for what is currently known as Special Attack and Special Defense, determining how much damage a Pokémon both receives and deals when special moves are used. As a result, a Pokémon could not be both strong with and weak against a Special attack, or vice versa, in the same way a Pokémon might have high Attack but low Defense. With Generation II, the Special stat was split into Special Attack and Special Defense, meaning Pokémon could have different base stat values for both, and those stats were both displayed on a Pokémon's stat screen; however, individual values and effort values remained unsplit, so that there was only a Special individual value and Special effort values, which affected both the Special Attack and Special Defense stats. Furthermore, Calcium increased both stats. In Generation III, IVs and EVs were finally given both Special Attack and Special Defense values as well, and the Calcium now worked on only Special Attack while the Zinc was introduced for the Special Defense.

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