I couldn't finish 'em. Looks like this's gonna get complicated.
Sandy is a boss in Final Fantasy IV: The After Years. She appears exactly as she did in Final Fantasy IV. Sandy will always cast Reflect on Cindy if she doesn't have it, and then will either use Haste on one of her party members, usually being Mindy, or Confuse on the player's party. She should be ignored in favor of defeating Cindy first.