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Disallow Defog
Disallow Rapid Spin
Disallow Stealth Rock
this pokemon's entire consept revolves around paving the way for other teammates and luring specific pokemon in to kill it. We don't want to be bringing in sabley or other ghosts which almost always carry Will-o-Wisp or Taunt which would almost certainly wall the setup sweepers we want to bring in. Note: my opinion will change if Cap19 gets a move that can hit the majority of ghosts hard
Allow Stealth Rock
Allow Defog
Disallow Rapid Spin
This seemed an easy decision for me. Stealth Rock will be useful, and Dragon Dancers hate hazards, and there is no point in running both, is there? Rapid Spin would be a bit over the top though, especially flavor-wise.