Blastoise - Bulky Spinner
Blastoise works well as a bulky spinner, utilizing it's amazing Def and SpD. Mostly Def. It's movepool is quite limited, though, but if you play it right you can use Roar/Dragon Tail mixed with Toxic to stall your opponent, while spinning hazards away.
Blastoise @ Leftovers
Trait: Torrent
EVs: 252 HP / 252 Def / 4 SpD
Bold Nature (+Def, -Atk)
- Rapid Spin
- Scald
- Toxic
- Roar / Dragon Tail
This set maxes out Blastoises role as a spinner, also using Toxic mixed with Roar or Dragon Tail to stall.
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Charizard - Sweeper
Charizard is great for sweeping, as it's SpA makes it a dangerous opponent. You can make it choiced, or put Life Orb on it. When choiced, you can just spam Fire Blast or Air Slash or something and totally sweep. Life Orb makes your choices a little wider, using SubRoost to heal the Sub/LO's damage, all the while attacking offensively with STAB move's.
Charizard @ Life Orb
Trait: Blaze
EVs: 4 HP / 252 SpA / 252 Spe
Timid Nature (+Spe, -Atk)
- Substitute
- Roost
- Flamethrower / Fire Blast
- Air Slash
This set abuses Charizard's great Special Attack while Roost'ing so you gain your HP back. Flamethrower or Fire Blast is you main STAB move, doing a lot of damage to everything that doesn't resist it, and Air Slash as a secondary STAB.
You can also have Specs Charizard, therefore making Charizard's big Special Attack even bigger. Instead of SubRoost, have Focus Blast and HP Ice or Grass, and there you go.
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Venusuar - Sweeper
Venusaur is good, but without Chlorophyll, (which you get in DW), Venusaur is less of a threat. Even so, Venusaur can still go all out as a sweeper, using it's big SpA to the fullest. Venusaur has a lot of great sets to look for, to many to list, so check Smogon's DP Venusaur list for all the great sets. http://www.smogon.com/dp/pokemon/venusaur