The complete Pokemon RBY pokedex, part 1

Pokémon Name: Blastoise
Type: Water
Classification: Turtle Pokemon
Pokédex Number: 009
Ability: Torrent – Increases power of Water-type moves by 1.5 if Pokemon has less than 1/3 HP remaining
Dream World ability: Rain Dish – User recovers 1/16 HP each turn during rain
Useful Attacks: Hydro Pump
Location Found:
D/P/P: Kanto starter - transfer from FireRed or LeafGreen, evolve from Wartortle
HG/SS: Evolve from Wartortle
B/W: Poke Transfer, Evolve from Wartortle

Charizard gets points for playing it safe and just being a dragon. Blastoise acts as his total opposite not only in type (fire vs. water), but also in execution - instead of evolving into a giant turtle, he transforms into a giant turtle with guns jutting out of his shell. It's a fantastic rivalry that still excites to this day. Blastoise, like his earlier forms, specializes in defense and special defense, and can allegedly smash concrete with his pressurized water blasts. He does have a small move set though - only three attacks learned after evolution, all of which are shared with Wartortle.

Evolution: From Wartortle at 36