Cast Wall on Asura, and she will not be able to use her cure spells on herself, and they will be cast on your characters. Make sure your party is at least level 35 or higher. Attack her with Rydia's best spells and use your best sword with Cecil. Use the Fire Saber because it damages her the most. Note: The Fire Saber is obtained from the Tower of Bable immediately after getting the Earth Crystal. The spell you want to use with Rydia is Virus. It does at least 700 if your characters are up to level. Also, if you have Kain, make him jump because he usually has the most HP -- he does not have to be cured from the reflected cure spells from Ausara. Note: The less people in your group when they get cured, the more HP that they will get back. In other words, Kain needs to be in the air at all times.