Question

What are the locations of all poison type Pokemon and all ground type Pokemon in heart gold before the elite 4?

Comments

https://bulbapedia.bulbagarden.net/wiki/List_of_Pok%C3%A9mon_by_Johto_Pok%C3%A9dex_number
I think all the poison and ground Pokemon on this list can be obtained before post-game, except Bulbasaur. Some of them are version exclusive, though.

Answer 1

Weedle, Kakuna, Beedrill: National Park
Spinarak: Routes 26, 27, 30, 31, 34, 35, 36, 37, 38, 39, 47, 48, New Bark Town, Cherrygrove City, National Park, Ecruteak City, Safari Zone Gate
Geodude, Graveler: Routes 45, 46, Dark Cave, Ruins of Alph, Union Cave, Mt. Mortar, Cliff Cave, Safari Zone, Victory Road
Zubat, Golbat: Routes 32, 33, 42, Dark Cave, Union Cave, Slowpoke Well, Ilex Forest, Burned Tower, Mt. Mortar, Cliff Cave, Safari Zone, Ice Path, Whirl Islands, Tohjo Falls, Victory Road
Sandshrew, Sandslash: Routes 26, 27, Union Cave, Safari Zone
Ekans, Arbok: Goldenrod Game Corner, Safari Zone
Wooper, Quagsire: Routes 26, 27, 32, Violet City, Ruins of Alph, Union Cave, Cliff Edge Gate, Cliff Cave, Safari Zone
Gastly, Haunter: Sprout Tower, Bell Tower, Safari Zone
Onix: Violet City, Union Cave, Cliff Cave, Safari Zone, Victory Road
Steelix: Cliff Cave
Bellsprout, Weepinbell: Routes 31, 32, 44, Safari Zone
Oddish, Gloom: Routes 47, 48, Ilex Forest, Safari Zone
NidoranF, Nidorina: Route 35, 36, Safari Zone
NidoranM, Nidorino: Route 35, 36, Safari Zone
Koffing, Weezing: Burned Tower, Rocket HQ, Safari Zone
Grimer: Safari Zone
Diglett: Route 48
Qwilfish: Route 32
Tentacool, Tentacruel: Route 26, 27, 32, 34, 40, 41, 47, New Bark Town, Cherrygrove City, Union Cave, Olivine City, Cianwood City, Whirl Islands
Gligar: Route 45
Swinub: Ice Path
Phanpy, Donphan: Route 45, Victory Road
Cubone, Marowak: Safari Zone
Rhyhorn: Safari Zone, Victory Road
Larvitar: Safari Zone
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