A Rotten Thirst (Assigned Quest)

Unlocking new quests in Monster Hunter: World requires a combination of in-game actions, including finding and capturing monsters across all ranks, engaging with villagers marked with a '!' in various hubs, and completing prior Optional quests. Additionally, fully researching monsters and hunting tempered variants contribute to your overall progress and quest availability.

To unlock new content, focus on these activities:

Finding a monster (low/high/master rank all count separately).
Capturing monsters (low/high/master rank all count separately).
Talking to Villagers with a (!) in Astera, Research Base, or Seliana.
Completing previous Optional quests.
Fully researching monsters (all tabs in the monster manual).
Hunting a certain number of different tempered monsters (quests/investigations with more than one tempered target only register the first listed).
Your current progress level for Assigned Quests.

The quest "Chef Quest! A Rotten Request" requires you to deliver 4 Forgotten Fossils. After completing quests, you will return to Astera to take your loot to the Smithy for forging weapons and armor. If you cannot make a full set, consider doing extra quests from the investigation team or continuing with your next assigned quest.