>>45820842Oddish and Bellprout are actually good, because you can get them so early. Makes it easy to live without a grass type until then, because you get bug and poison types to try in the mean time.
Water is the most common type Pokemon you can get in gen 1. You can buy one super early with Magikarp, get one from Eevee, get 3 free fishing rods, and get a free Lapras to make sure someone isn't softlocked from surfing. Squirtle is cool, but there's no need to take a water starter, because you are swimming in options.
Eevee is your only chance for an early fire type, which makes Charmander really appealing.
You use Oddish and Bellsprout, because you correctly chose Charmander.
