BULBASAUR:Starter Pokemon (Level 5)
CHARMANDER:Starter Pokemon (Level 5)
SQUIRTLE:Starter Pokemon (Level 5)
EEVEE:Celadon Mansion (Level 25)
HITMONLEE:One of two Pokemon obtained in the Fighting Dojo in Saffron City (Level 30)
HITMONCHAN:One of two Pokemon obtained in the Fighting Dojo in Saffron City (Level 30)
MEW:Not normally obtainable except through Nintendo promotions, though a stable method for encountering is now available.
ARTICUNO:Seafoam Islands (Level 50)
ZAPDOS:Power Plant (Level 50)
MOLTRES:Victory Road (Level 50)
AERODACTYL:Resurrected from Old Amber in Cinnabar Lab (Level 30)
OMANYTE:Resurrected from Helix Fossil in Cinnabar Lab (Level 30)
KABUTO:Resurrected from Dome Fossil in Cinnabar Lab (Level 30)
LAPRAS:Silph Co. (Level 25)
SNORLAX:West of Celadon City and on east side of Route 11 (Level 30)
MEWTWO:Cerulean Cave (Level 70)
VOLTORB:Appears as item balls six times in Power Plant (Level 40)
LICKITUNG:Internal trade between Cycling Road and Fuchsia City
JYNX:Internal trade in Cerulean City
MR. MIME:Internal trade on Route 2
TANGELA:Internal trade in Cinnabar Island
ELECTRODE:Internal trade in Cinnabar Island
SEEL:Internal trade in Cinnabar Island
FARFETCH'D:Internal trade in Vermilion City
NIDORANfE:Internal trade in Route 5 Underground Path gate
NIDORINA:Internal trade in gate on Route 11
ABRA:Game Corner prize (Level 6, 120 coins)
CLEFAIRY:Game Corner prize (Level 12, 750 coins)
NIDORINO:Game Corner prize (Level 17, 1200 coins)
PINSIR:Game Corner prize (Level 20, 2500 coins)
DRATINI:Game Corner prize (Level 24, 4600 coins)
PORYGON:Game Corner prize (Level 18, 6500 coins)