Final Fantasy III/World of Darkness

Suggested team:
 * Magus or Devout
 * Ninja
 * Onion Knight
 * Sage

Go for an all-out!

The Sage's summon Titan will get rid of any group of monsters, the Magus' Death and Break2 spells will get rid of any single monster. Equip the Ninja with the Moonring boomerang and keep him in the back row. The Onion Knight has the best armor, so he can stay in the front row.

Free the four Warriors of Darkness
Against the Xande Clones and the other bosses use Ninja's shurikens and Sage's Bahamut, but also let the Devout cast Haste on the Onion Knight. The enemies should go down in two turns.

Final boss: Cloud of Darkness
The final boss is quite stronger: after the Devout cast Haste on the Onion Knight, make him cast Cure4 on everyone at every turn.