Generation IV, what changed

Generation IV split physical and special by move

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Generation IV made physical or special a property of each move instead of its type, starting with Diamond and Pearl in Japan on 28 September 2006 for the Nintendo DS. The games added 107 species for a total of 493. Platinum followed in 2008, and HeartGold and SoulSilver remade the Johto games in 2009.

Generation IV: Diamond, Pearl, Platinum, HeartGold and SoulSilver. Main-series games only.

Types17

Stat formulaIVs, EVs, nature

Physical and specialBy move

BreedingDay Care, Masuda method

Battle mechanicPhysical and special split per move

GamesDiamond, Pearl, Platinum, HeartGold, SoulSilver

The defining change

Every move received its own physical or special category

Before the split, every Fire, Water, Grass, Electric, Ice, Psychic, Dragon and Dark move was special, and every move of the other types was physical.
Fire Punch, Ice Punch and Thunder Punch became physical, and Shadow Ball became special.
Moves that hit more than one target dealt 0.75 times damage, up from 0.5 times.
Struggle became typeless and cost one quarter of the user's maximum HP.

No type arrived, but older species evolved into new typings

No new types arrived; the chart stayed at 17.
Several older species gained evolutions that changed type, such as Magneton to Magnezone and Eevee to Leafeon and Glaceon.

Sandstorm gave Rock types a Special Defense bonus

Sandstorm began raising the Special Defense of Rock types by 1.5 times.

Eggs hatched at level 1 and the Masuda method began

Eggs hatched at level 1 instead of level 5.
The Masuda method gave eggs from parents of two languages five shiny rolls, about 1 in 1,638.
Pal Park moved Pokémon from Generation III cartridges in the DS slot.

Stealth Rock, Trick Room and the Global Trade Station arrived

Stealth Rock, Toxic Spikes and Trick Room arrived.
New held items included Life Orb, Choice Specs and Choice Scarf.
The Global Trade Station allowed trades with strangers online through Nintendo Wi-Fi Connection.
Diamond and Pearl added evolutions by location, by known move and by held item at a time of day.

Day and night returned and Defog joined the HMs

The day and night cycle returned, in five periods.
Defog joined the HM list in Diamond and Pearl.

Dialga, Palkia and Giratina split the three Sinnoh releases

Diamond featured Dialga and Pearl featured Palkia.
Platinum added Giratina's Origin Forme, the Distortion World, Rotom's appliance forms and a Battle Frontier.
HeartGold and SoulSilver had the lead Pokémon follow the player and shipped with the Pokéwalker pedometer.
A Generation III cartridge in the DS slot changed some wild encounters in Diamond, Pearl and Platinum.

3 releases, 2006 to 2009

2006Diamond and PearlNintendo DS
2008PlatinumNintendo DS
2009HeartGold and SoulSilverNintendo DS

Type chart era

17 types in the Generations II to V chart

Battles in these games follow that chart, shared with the rest of Generations II to V. Open the type chart by era

Generation IV learnset tabs show each move's own category

Learnset tabs Diamond-Pearl, Platinum and HeartGold-SoulSilver mark each move physical, special or status by move rather than by type.
Earlier tabs label category by type, so the same move can carry a different category in an earlier tab.
The matchup column is the same Gen II to V chart as before.
Evolution rows for Magnezone, Leafeon and Glaceon carry location conditions that later games changed.