I mean, seriously: Bulbasaur Ivysaur Venusaur Weedle Kakuna Beedrill Zubat Golbat Oddish Gloom Vileplume Bellsprout Weepinbell Victreebel Venonat Venomoth Koffing Weezing Ekans Arbok Nidoran (male and female) Nidorino Nidorina Nidoqueen Nidoking Tentacool Tentacruel Gastly Haunter Gengar That's 31 Pokemon or a whopping 21% of the original 151. It's interesting because Poison wasn't even a viable type back when it was introduced. The only type it could hit super-effectively was Grass...which amounted to an enemy Tangela since all the other Grass types lacked a Poison weakness. Consequently, it had more weaknesses than resistances or advantages. Not to mention, they had horrible and basically nonexistent STAB moves to damage opposing Pokemon with. I just realized all of this recently because I'm trying to make a new, theoretical Kanto game and the myriad of Poison types suddenly became explicit. Anyways, why do you think there were so many made? Any of these listed Pokemon you feel shouldn't have been classified as Poison?