How do you get the dualcast augment in final fantasy IV ds?

Answer 1

You need to have given Palom and Porom three Augments, at least one each (so one for one, two for the other). Then after they leave the party, talk to the elder in Mysidia, who will give you the Cry, Bluff, Twincast and Dualcast augments.

Answer 2

Dualcast is one of the Red Mage's learnable skills. It requires 999AP to learn, which is the highest requirement of any skill. Also to get to that stage, you must also learn the three previous skills, Red Magic 1, 2 and 3, a total of 160AP.

Answer 3

only viera red mages can learn it

http://www.gamefaqs.com/ds/937330-final-fantasy-tactics-a2-grimoire-of-the-rift/answers?qid=19279