Catching all types of Pokemons is not the only goal in "Pokemon GO." If you really want to be a Pokemon Master, you must win battles in Pokemon gyms. However, in order to do that, players must acquire strong Pokemons first like Slowbro, Venusaur and Vaporeon.
Having a Slowbro, Venusaur and Vaporeon is a really huge advantage when battling a gym because these Pokemons are one of the strongest creatures in "Pokemon GO." Using these Pokemons gives you a higher chance to win gym battles. As Mirror stated, the overall point of owning, attacking and defending a Pokemon gym is to gain Pokecoins that can be used to buy in-game items.
To obtain a Vaporeon, "Pokemon GO" players can just easily evolve them using Eevee's. As stated in our previous report, players can rename the Eevee's name to "Rainer" if they want to evolve it to Vaporeon. Change the Eevee's name to Pyro if you want to evolve it to Flareon, and if you want to evolve Eevee to an electric-type Pokemon, rename the Eevee you'll evolve to Sparky and it'll evolve as Jolteon.
Slowbro is a water type Pokemon so players can probably catch this Pokemon near bodies of water. If players are having a hard time catching Slowbro, you can always choose to evolve a Slowpoke. According to "Pokemon GO" Database, it requires 50 Slowpoke candies to evolve a Slowbro.
However, there is no still no exact location where to find a Venusaur. This Pokemon might be really hard to catch because it is the final evolution of Bulbasaur. "Pokemon GO" players can evolve Bulbasaur into an Ivysaur using 25 candies, and evolve and Ivysaur into a Venusaur afterwards by using 100 candies as indicated in the list of Pokemons in "Pokemon GO" database.
