Clefable

Clefable is an underrated sweeper that usually flies under the radar. It is only limited by the amount of maintenance required to set it up, which usually is done by paralyzing most of the opposing team and killing any Ghost-types that may be in the area. It is more durable than one might expect due to its nice and plump HP and decent Special Defense. Clefable can take over the game early on, but this will not likely lead to a clean sweep. Best used either as a mid-to-late-game sweeper or in conjunction with a more versatile sweeper such as Charizard or Tentacruel to help pound away at the opponent's defenses until they crack.