Generation II added Dark and Steel and split Special in two

Gold and Silver corrected four Generation I matchups

• Ghost became 2 times effective against Psychic.
• Bug became 0.5 times against Poison, and Poison became neutral against Bug.
• Ice became 0.5 times against Fire.

Special Attack and Special Defense became separate stats

• Special split into Special Attack and Special Defense.
• Critical hits moved to a fixed 1 in 16 base rate and dealt 2 times damage.
• Held items added flat battle effects, such as Leftovers restoring one sixteenth of maximum HP each turn.

The Day Care introduced eggs, gender and shiny Pokémon

• The Route 34 Day Care introduced breeding, eggs, egg groups and egg moves.
• Gender arrived, set by the Attack DV.
• Shiny Pokémon arrived at 1 in 8,192, set by DVs, which made a shiny parent pass a 1 in 64 chance to its offspring.
• Pokérus first appeared, doubling stat experience gains.

A real-time clock and held items arrived

• A real-time clock added day and night, weekday events and time-based evolutions.
• Friendship arrived, with Return, Frustration and friendship evolutions such as Golbat to Crobat.
• Weather moves arrived: Rain Dance, Sunny Day and Sandstorm.
• Kurt in Azalea Town made Poké Balls from Apricorns.

Freeze and Hyper Beam lost their Generation I behaviour

• Frozen Pokémon could thaw at random, at about 10 percent per turn.
• Hyper Beam required a recharge turn even after a knockout.
• Bug moves gained power, with Megahorn at 120.

Crystal added a female player and the first move tutor

• Gold exclusives included Mankey, Spinarak, Gligar, Teddiursa and Mantine; Silver exclusives included Vulpix, Ledyba, Delibird, Skarmory and Phanpy.
• Crystal added the first selectable female player character.
• Crystal added animated battle sprites, the Battle Tower and the first move tutor, who taught Flamethrower, Thunderbolt and Ice Beam.
• Crystal's story centred on Suicune.

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