Not every character has a spot dodge that can be spammed. Some characters like DDD, Rob, Pit or Luigi are invincible and can't be stopped when they do it. Marth gets raped so hard by spot dodging it's not even funny. I would never even think about playing Shea or Ivo in a serious set with Marth because of their dodging. Characters with quick hitboxes like Marth's can't do anything about dodging.
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