The.legend.of.heroes.sen.no.kiseki.i.kai.build.... Now

Keep these casters in the back. Use their high ATS to wipe out mobs before they can move.

Pandora (increases Arts damage and area of effect) or Criminal (high critical rate for Fire arts). The.Legend.of.Heroes.Sen.no.Kiseki.I.KAI.Build....

Force (recovers CP upon defeating enemies) or Tauros (massively increases damage but slows down the user). Keep these casters in the back