With Gold and Silver, the number of types goes from 15 to 17: Dark and Steel make their entrance to rebalance a game where Psychic Pokémon reigned unchallenged. Here is the complete second-generation effectiveness chart, followed by a type-by-type summary of weaknesses.
The type chart
Read the chart row by row: the row is the type of the attack, the column is the type of the Pokémon receiving it. ×2: super effective; ½: not very effective; 0: no effect. Against a dual-type Pokémon, the multipliers combine (×4, ×1, ¼…).
| Attack ↓ / Defense → | Normal | Fire | Water | Grass | Electric | Ice | Fighting | Poison | Ground | Flying | Psychic | Bug | Rock | Ghost | Dragon | Dark | Steel |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Normal | ½ | 0 | ½ | ||||||||||||||
| Fire | ½ | ½ | ×2 | ×2 | ×2 | ½ | ½ | ×2 | |||||||||
| Water | ×2 | ½ | ½ | ×2 | ×2 | ½ | |||||||||||
| Grass | ½ | ×2 | ½ | ½ | ×2 | ½ | ½ | ×2 | ½ | ½ | |||||||
| Electric | ×2 | ½ | ½ | 0 | ×2 | ½ | |||||||||||
| Ice | ½ | ½ | ×2 | ½ | ×2 | ×2 | ×2 | ½ | |||||||||
| Fighting | ×2 | ×2 | ½ | ½ | ½ | ½ | ×2 | 0 | ×2 | ×2 | |||||||
| Poison | ×2 | ½ | ½ | ½ | ½ | 0 | |||||||||||
| Ground | ×2 | ½ | ×2 | ×2 | 0 | ½ | ×2 | ×2 | |||||||||
| Flying | ×2 | ½ | ×2 | ×2 | ½ | ½ | |||||||||||
| Psychic | ×2 | ×2 | ½ | 0 | ½ | ||||||||||||
| Bug | ½ | ×2 | ½ | ½ | ½ | ×2 | ½ | ×2 | ½ | ||||||||
| Rock | ×2 | ×2 | ½ | ½ | ×2 | ×2 | ½ | ||||||||||
| Ghost | 0 | ×2 | ×2 | ½ | ½ | ||||||||||||
| Dragon | ×2 | ½ | |||||||||||||||
| Dark | ½ | ×2 | ×2 | ½ | ½ | ||||||||||||
| Steel | ½ | ½ | ½ | ×2 | ×2 | ½ |
What has changed since Red and Blue
- Two new types: Dark (immune to Psychic, super effective against Psychic and Ghost) and Steel (which resists eleven types and only fears Fire, Fighting and Ground).
- Ghost finally hits Psychic: in Red and Blue, a programming error made Ghost moves have no effect on Psychic.
- Bug and Poison: Bug moves are no longer super effective against Poison (they are even not very effective), and Poison is no longer super effective against Bug.
- Ice against Fire: Ice is now not very effective against Fire.
- Special is split in two: each Pokémon now has a Special Attack and a Special Defense.
Weaknesses and resistances by type
| Type | Weak to | Resists | Immune to |
|---|---|---|---|
| Normal | Fighting | — | Ghost |
| Fire | Water, Ground, Rock | Fire, Grass, Ice, Bug, Steel | — |
| Water | Grass, Electric | Fire, Water, Ice, Steel | — |
| Grass | Fire, Ice, Poison, Flying, Bug | Water, Grass, Electric, Ground | — |
| Electric | Ground | Electric, Flying, Steel | — |
| Ice | Fire, Fighting, Rock, Steel | Ice | — |
| Fighting | Flying, Psychic | Bug, Rock, Dark | — |
| Poison | Ground, Psychic | Grass, Fighting, Poison, Bug | — |
| Ground | Water, Grass, Ice | Poison, Rock | Electric |
| Flying | Electric, Ice, Rock | Grass, Fighting, Bug | Ground |
| Psychic | Bug, Ghost, Dark | Fighting, Psychic | — |
| Bug | Fire, Flying, Rock | Grass, Fighting, Ground | — |
| Rock | Water, Grass, Fighting, Ground, Steel | Normal, Fire, Poison, Flying | — |
| Ghost | Ghost, Dark | Poison, Bug | Normal, Fighting |
| Dragon | Ice, Dragon | Fire, Water, Grass, Electric | — |
| Dark | Fighting, Bug | Ghost, Dark | Psychic |
| Steel | Fire, Fighting, Ground | Normal, Grass, Ice, Flying, Psychic, Bug, Rock, Ghost, Dragon, Dark, Steel | Poison |
