How to Complete A Request
Part 1
The objective of this quest is to defeat Illua. The law forbids getting robbed, but this doesn't matter, because Illua sends the judge away before the battle begins.
Illua has the Dimensional Rift ability, which removes 75% of the targets' HP. It is an area effect spell, so it can damage a lot of units at once. Avoid standing near each other to try to limit the damage from that, and be prepared to do a lot of healing with magick and items.
Part 2
After you defeat Illua, you end up in another dimension (the one Luso has seen in his dreams) and you are attacked by a giant hand known as a Neukhia. The law forbids the use of Opportunity Commands, which include things like "Fleet of Foot!" and "Flurry!" and "Battle Shout!"
There are some purple glowing things at the sides of the battlefield. If a unit stands next to it, he or she can use the "Charge" command, which charges up a magickal cannon. After charging all of the purple things, the cannon will fire, doing a large amount of damage to all enemy units. "Charge" is not an Opportunity Command, so you won't break the law if you use it.
Of course, you can also do damage to the enemy units with regular weapon and magickal attacks.
There are two Plagues, which look like yellow Ahrimans. They and the Neukhia can both cause Confusion on your units. You do not need to kill the Plagues; just the Neukhia.
The Neukhia has abilities to damage many units with a single move, as well as an ability to set multiple units' MP to 0.