Just what the title says.
Mine personally would be Team Rocket. Not just because they had the coolest battle music, but they also had the coolest outfits. Personally I think the following villains all look a bit much like clowns (Especially Team Galactic. Crazy hair anyone?). It's quite disappointing but perhaps with Heart Gold and Soul Silver Team rocket will come back.
Not that the third and fourth gen organisations are too bad (More challenge to fight than just Team Rocket and poison pokemon) but they do seem a bit off.
Team Rocket counts for both gen 1 and gen 2, and Team Magma/Aqua are bundled together because they're generally the same.
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