I recommend to use your Ampharos because that way you will also have the type-advantage against charizard and lapras. (grass wont work on lapras because its water-ice)
Blastoise is weak against Grass and Electric-type attacks.
Have a diverse team, make sure there isn't a type that is super effective against all your pokes. -Blastoise -Gengar --Alakazam -Pidgeot -HM Pokemon X2 -Blastoise is super effective against rock, ground and fire -Gengar is super effective against ghost,grass and bug -Alakazam is super effective against fighting and poison -Pidgeot is super effective against bug fighting grass
Grass and Electric moves
Blastoise is a Water Type Pokemon. It evolves from Squirtle and Wartortle, also water types. Squirtle is the Water Type starter Pokemon from Kanto.
For the elite 4 you need: A good electric pokemon (Probably Pikachu, Riachu or Zapdos), A good psychic pokemon (Probably Kadabra or Alakazam), A good water or grass pokemon (Blastoise is good, as would be Venasaur) and a good ice pokemon (Articuno is good, as are Dewgong and Lapras). If it is your first time and blastoise was your starter, moltres or Arcanine will be useful for your rival
Grass, and electric.
Blastoise is weak against Grass and Electric-type attacks.
electric types and grass types.
In this case, Blastoise is the best. Charizard has a better advantage against Venusaur because Charizard is a Fire Type and Venusaur is a Grass Type. Still, he has no chance against Blastoise because he is a Fire Type and Blastoise is a Water Type, so overall, Blastoise is the best.
Have a diverse team, make sure there isn't a type that is super effective against all your pokes. -Blastoise -Gengar --Alakazam -Pidgeot -HM Pokemon X2 -Blastoise is super effective against rock, ground and fire -Gengar is super effective against ghost,grass and bug -Alakazam is super effective against fighting and poison -Pidgeot is super effective against bug fighting grass
Grass and Electric moves
Ice , Electric , grass and low chops, and karake chops ,
Blastoise is a Water Type Pokemon. It evolves from Squirtle and Wartortle, also water types. Squirtle is the Water Type starter Pokemon from Kanto.
Electric and Grass.
Your team is too weak to Water, Electric and Grass. You should replace Blastoise with maybe a Dragonite.
They are all equal in power, it just depends on what type you prefer to work with. If you are good with water pokemon choose Blastoise. If you are like me then you love fire and you should go with Charizard. But if grass types are you thing then Venasaur is your pokemon. They all have their own pros and cons just like with any other pokemon.
For the elite 4 you need: A good electric pokemon (Probably Pikachu, Riachu or Zapdos), A good psychic pokemon (Probably Kadabra or Alakazam), A good water or grass pokemon (Blastoise is good, as would be Venasaur) and a good ice pokemon (Articuno is good, as are Dewgong and Lapras). If it is your first time and blastoise was your starter, moltres or Arcanine will be useful for your rival