To initiate the Heart of the Marsh quest in New World, a player must speak with an NPC named Nekumanesh in the Cutlass Keys location. In this quest, you will need to learn what happened to Nekumanesh's wife, Jocelyn.
The first thing a player needs to do is find out what is going on with Jocelyn. Players can accomplish this by traveling to the Salty Marshes to the southwest corner of the map.
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After arriving at the quest's waypoint, the player must wait until the Marshjaw creature spawns. It is a required kill to finish the quest. After slaying the beast and looting it, you will pick up Jocelyn's Diary—a quest item.
After defeating and looting the monster, you need to return to Nekumanesh and talk to him. This conversation will end the quest, and you will receive your rewards. You will earn an Adventurer’s Ring, 1830 XP, 105 Coins, 250 Standing, and 20 Azoth.
Note: Some players experienced inconsistencies with the Marshjaw monster spawning. It is most likely due to a bug and needs fixing by the developer.
For more articles and guides on New World, make sure to check out How to play the New World Public Test Realm and How to fix the request throttled error in New World? on Pro Game Guides.