When you enter the Vigga Marshes to complete the quest for Torus, as you descend into the area, you come across your first boss of the Greak: Memories of Azur, Glekt Kahnem.
When you first see him, he's stealing something from a mechanism to open the gate on the other side. They swiftly disappear, and you get attacked by some of his minions, Urlag Scouts. Each wave of his minions has to die to fight Glekt, which also means the Plague monsters.
The Urlag Scouts use Blowpipes, which the arrows upon fired will home in at you, so they'll follow you. This is incredibly dangerous due to only having four life points. But the arrows will shatter upon impact with stone, and the platforms of this arena are stone. So keep moving, never stop.
These enemies will disappear upon you getting too close and want to maintain a distance from you. The best way to attack is by your downward slash attack—jump + down + attack—you learned from Zack for completing his first quest —Scout Training. This deals massive damage, and the waves will be defeated in no time.
After the waves, the boss, Glekt Kahnem, will enter the fray. Deal with him the exact same way you dealt with his minions. Although it has a larger health bar, the only difference is they can summon Plague Bats, but if you use your downward slash attack, this should kill the bat as soon as it spawns. Sure, the boss is quicker than his warriors but is not much harder to kill.
Upon defeat, they'll drop the Silver Crest to open the door to the east.
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