You reach Nohr via a hidden passage in Burning Falls, but are attacked on the streets.
Defeat the Boss
The boss unit is at the north of the map, but there are many enemy units to deal with. Some will drop items when they are defeated.
There is a Launcher in the southwest of the map that can be used by Shuriken-wielding units. The southeast has a Fire Orb that your tome/scroll-wielders can use.
In the center of the map, there are four Dragon Veins that your royal units can use to heal up everyone who is in the center of the map, including enemies.
Reinforcements will show up throughout the battle, but none of them will drop any items.
In the north part of the map, there are some Ballistas that your bow-wielding units can use. The boss unit might also come down and use one if you get in his range.
After you defeat the boss unit, the battle will end.