Tera Walkthrough: Essence and Sensibility
Talk to Researcher Dulari in Dulari's Camp to begin this quest. This is a level 3 quest.
Essence and Sensibility
The "arsenal" you're wielding tells me all I need to know about you. You're here to fight, not to learn. However, I believe you can do both. These ghilliedhus have abnormal essences. You need more experience in recognizing what's wrong before you can do what's right. Are you ready to dispel your ignorance with some improvisational forestry?
Accept his quest. He tells you that taking out those trees is the last thing he will ask for you. You need to obtain Heartwood Essence from elder or hardened Ghilliedhus. Not that these are not the normal Ghilliedhus you needed for previous quests. The hardened and elder ones are a bit south of his camp. These are tougher then the previous Ghilliedhus you had dealt with, so watch your health to make sure they don't kill you. They hit hard, but slow. So a good strategy is to attack them with what you have got, then as soon as they are preparing to strike you, retreat out of their melee range, then repeat the process. If you have health potions on you, get them ready in case your health gets critically low.
After you have collected all five Heartwood Essences, return to Dulari at his camp. He tells you that you might just make it as a researcher after all. If you can get through life without your weapons. His watchdogs, Hellier and Clovis, ask that you keep using them while longer. When you are ready, see what they want.
You get 90 copper and 900 xp for completing this quest. Make sure to scout the area for some more quests, including the "Garrison in Distress" quest from Dulari, as well as quests from other NPCs nearby.