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Although all Pokémon up to the third generation can be recruited, some have to be unlocked by completing a certain mission first. The version exclusives for each game are those Pokémon whose pre-recruitment missions occur naturally. To obtain the Pokémon in the other version, you must use the Wonder Mail code for the relvant mission.

[edit] Blue Version

Name	Type(s)	Area	Floor(s)	Size	Recruitment %
Magikarp	Water	Waterfall Pond	7-11	*
Gyarados	Water/Flying	Evolves from Magikarp at lv. 20		****
Lapras	Water/Ice	Far-off Sea	45-50	****
Aipom	Normal	Uproar Forest	1-6	*
Porygon 2	Normal	Buried Relic Wish Cave Joyous Tower Evolves from Porygon with an Upgrade and a Cable link	10-14, 16-18 79-84 80-84	*
Minun	Electric	Thunderwave Cave Lightning Field Joyous Tower Purity Forest	4-5 7-19 5-8 10-12	*

[edit] Red Version

Name	Type(s)	Area	Floor(s)	Size	Recruitment %
Feebas	Water	Waterfall Pond	16-19	*
Milotic	Water	Evolves from Feebas with Beauty Scarf		****
Mantine	Water/Flying	Grand Sea	30	**
Roselia	Grass	Uproar Forest	4-7	*
Porygon	Normal	Buried Relic	5-10	*
Plusle	Electric	Thunderwave Cave Lightning Field Joyous Tower Purity Forest	4-5 7-19 5-8 10-12	*