Some Pokémon aren’t found in tall grass: they are given by a character, traded for another, bought at the Game Corner or met only once. Missing them can sometimes make the Pokédex impossible to complete without trading. Here is the complete list, version by version.
Gift Pokémon
Your starter Pokémon, the Togepi Egg, Bill’s Eevee, the Tyrogue from Mt. Mortar, the Shuckle from Cianwood City (lent to you, you’ll have to give it back) and the messenger Spearow on Route 35: so many companions given to you as the story unfolds. In Crystal, the Dratini from Dragon’s Den and the Mystery Egg from the Day-Care are added.
| Pokémon | Location | How | Versions |
|---|---|---|---|
 Dratini | Dragon's Den | Given · No. 15 | Crystal |
 Chikorita | New Bark Town | Given (starter Pokémon) · No. 5 | All |
 Cyndaquil | New Bark Town | Given (starter Pokémon) · No. 5 | All |
 Totodile | New Bark Town | Given (starter Pokémon) · No. 5 | All |
 Eevee | Goldenrod City | Given · No. 20 | All |
 Shuckle | Cianwood City | Given · No. 15 | All |
 Togepi | Violet City | Given, by Professor Elm's aide | All |
 Tyrogue | Mt. Mortar | Given, in the basement · No. 10 | All |
 Pichu | Route 34 | Given, as an Egg · No. 5 | Crystal |
 Cleffa | Route 34 | Given, as an Egg · No. 5 | Crystal |
 Igglybuff | Route 34 | Given, as an Egg · No. 5 | Crystal |
 Tyrogue | Route 34 | Given, as an Egg · No. 5 | Crystal |
 Smoochum | Route 34 | Given, as an Egg · No. 5 | Crystal |
 Elekid | Route 34 | Given, as an Egg · No. 5 | Crystal |
 Magby | Route 34 | Given, as an Egg · No. 5 | Crystal |
 Spearow | Route 35 | Given · No. 10 | All |
In-game trades
Several townspeople offer a trade. The Pokémon you receive carries the name and ID of its former Trainer: it gains more experience, but only obeys you if you have the necessary Badges.
| Pokémon | Location | How | Versions |
|---|---|---|---|
 Rapidash | Pewter City | Trade, for Gloom | Gold, Silver |
 Xatu | Pewter City | Trade, for Haunter | Crystal |
 Magneton | Abandoned Power Plant | Trade, for Dugtrio | Crystal |
 Machop | Goldenrod Dept. Store | Trade, for a Drowzee | Gold, Silver |
 Machop | Goldenrod Dept. Store | Trade, for an Abra | Crystal |
 Onix | Violet City | Trade, for Bellsprout | All |
 Voltorb | Olivine City | Trade, for Krabby | All |
 Aerodactyl | Route 14 | Trade, for Chansey | All |
 Dodrio | Blackthorn City | Trade, for a female Dragonair | Crystal |
 Rhydon | Blackthorn City | Trade, for a female Dragonair | Gold, Silver |
Game Corner prizes
The Goldenrod City and Celadon City Game Corners exchange coins for Pokémon. The prizes differ between Gold, Silver and Crystal.
| Pokémon | Location | How | Versions |
|---|---|---|---|
 Pikachu | Celadon Game Corner | To buy · No. 25 | Crystal |
 Mr. Mime | Celadon Game Corner | To buy · No. 15 | Gold, Silver |
| Eevee | Celadon Game Corner | To buy · No. 15 | Gold, Silver |
 Porygon | Celadon Game Corner | To buy · No. 20 | Gold, Silver |
 Porygon | Celadon Game Corner | To buy · No. 15 | Crystal |
 Larvitar | Celadon Game Corner | To buy · No. 40 | Crystal |
 Ekans | Goldenrod Game Corner | To buy · No. 10 | Gold |
 Sandshrew | Goldenrod Game Corner | To buy · No. 10 | Silver |
 Abra | Goldenrod Game Corner | To buy · No. 10 | Gold, Silver |
 Abra | Goldenrod Game Corner | To buy · No. 5 | Crystal |
 Cubone | Goldenrod Game Corner | To buy · No. 15 | Crystal |
 Dratini | Goldenrod Game Corner | To buy · No. 10 | Gold, Silver |
 Wobbuffet | Goldenrod Game Corner | To buy · No. 15 | Crystal |
One-time encounters
These Pokémon only appear once: save before the battle. If they faint, they are lost (except for Pokémon that reappear on a fixed date, such as Lapras every Friday).
| Pokémon | Location | How | Versions |
|---|---|---|---|
 Celebi | Ilex Forest | Encounter (GS Ball required) · No. 30 | Crystal |
 Lapras | Union Cave | Special · No. 20 | All |
 Gyarados | Lake of Rage | Encounter · No. 30 | All |
 Sudowoodo | Route 36 | Special · No. 20 | All |
 Suicune | Bell Tower | Encounter · No. 40 | Crystal |
 Ho-Oh | Bell Tower | Encounter · No. 40 | Gold |
 Ho-Oh | Bell Tower | Encounter · No. 70 | Silver |
 Ho-Oh | Bell Tower | Encounter · No. 60 | Crystal |
 Lugia | Whirl Islands | Encounter · No. 70 | Gold |
 Lugia | Whirl Islands | Encounter · No. 40 | Silver |
 Lugia | Whirl Islands | Encounter · No. 60 | Crystal |
- Snorlax, asleep in front of Diglett’s Cave near Vermilion City, wakes up to the sound of the Poké Flute (level 50).
- The three Electrode at the generator in the Team Rocket HQ in Mahogany Town can be caught.
- Raikou, Entei (and Suicune in Gold and Silver) roam Johto at level 40: see the legendary Pokémon.
