Find the Fortress and loot the chest.
Loot and Tips
The fort itself is easy to find. If you having problem to find due to terrain or trees, try to find the waving flag on its top. Inside of it, you will have to face Greenhorn Grunts, Red Gruntkings and Fiery Roarcs. The chest will contain 3x Energy Crystals and other drops based on event's level. Three Crest of the Strongarms can be looted here, one in front of each entrance of the fort and the last one near the chest.
- In case you don't want to face any of the creatures, you can rush to the chest, loot it and reenter the island. All the structures will still be in place but not the foes.