Which Pokémon was the first shown in the National Pokédex?

Bulbasaur is the first Pokémon shown in the National Pokédex.

Its National Pokédex number is 001, followed by Ivysaur at 002 and Venusaur at 003. Bulbasaur is one of the three original starter Pokémon offered by Professor Oak in Pokémon Red, Green, Blue, and their related versions.

Bulbasaur is classified as a dual Grass- and Poison-type Pokémon. A seed is planted on its back at birth, and the game descriptions explain that the seed grows as Bulbasaur develops. At level 16, Bulbasaur evolves into Ivysaur, which later evolves into Venusaur at level 32.

Pikachu is more recognizable as the franchise mascot, but it is number 025 rather than number 001. Charmander and Squirtle are the other two original Kanto starters, while Mew is the final entry in the original National Pokédex sequence.