Besides trying to complete the main story quests in Mandragora: Whispers of the Witch Tree, you can also pick up several side quests to help you get around. If you speak to Gerald, he might tip you off about a Vampire lurking in a nearby lair, thus starting the Relic Hunters quest. It is up to you to find and defeat this particular enemy to get some rewards. This guide will cover how to complete the Relic Hunters quest in Mandragora Whispers of the Witch Tree.
How To Complete Relic Hunters Quest In Mandragora

To start the Relic Hunters quest, talk to Gerald after recruiting him to your Witch Tree. He will join you at your base after completing the Let the Right One In quest. He will then talk about a Vampire Lair nearby, and your task is to explore and kill whatever is inside it.
Paleweaver Location and How to Beat

Next, make your way west towards the Ruins of West Wickham and enter the sewers to the south of the Ruins waypoint. After activating the West Wickham Sewers waypoint, head east to find the Paleweaver boss. The Paleweaver will mostly lunge at you to attack, and will shoot poison. Both attacks are easy to dodge around, and you can quickly get behind the boss to avoid its attack.
While fighting the boss, focus on hitting the bulbous portion on its body. That will require you to roll around the boss and hit from behind. Just be careful not to get any of the poison that it keeps shooting. Once the boss is down to less than half health, it will summon miniature spiderlings to fight on its behalf. Attack the spiderlings first before going for the boss, as you can easily become outnumbered. Keep rolling behind the boss and hit its abdomen till it is dead.
Return to Gerald to claim your rewards, which are 300 Gold and 2x Lockpick. This will complete the Relic Hunters quest, but you can also pick up some more quests in Mandragora: Whispers of the Witch Tree, like the Old Regrets Quest or the Talking Skull Quest.