After escaping the trap, a servant of Anankos appears, disguised as a familiar face.
Before the Battle
Again, there are more chests than chest keys, so you should include some Locktouch units in this fight.
The battle takes place in a forest. Your flying units can fly right over the trees, but you are more likely to succeed if you keep your units together. Use the Dragon Veins to burn through the trees, allowing your Locktouch units to open up the chests inside the forests.
The easternmost Dragon Veins can only be accessed from inside of the forest, so you will need to keep burning the trees in order to make it through to the east side of the map.
The chests contain very rare items, so you should open them all.Once you reach the east side of the map, you can battle the boss unit to end the chapter.