U'odh Nunh won't help you until you prove your skill with another dangerous task.
This quest is available if you have completed the quest Trial by Turtle, and have reached level 31.
Starting the Quest
Talk to U'odh Nunh in the Forgotten Springs in Southern Thanalan to begin the quest.
Use the Spear to Lure out the Amalj'aa Veteran
Go to where the orange arrow is pointing on the minimap. Target the sparkling Destination and use the Bloody Guisarme from the Key Items section of your inventory or via the icon next to the quest name in your list of active quests.
Lie in Wait
Go to the purple glowing Destination and check on it. Stonespike Tanadd Gah will attack. Defeat him.
Present the Veteran's Necklace
Go back to the Forgotten Springs and talk to U'odh Nunh to hand over the necklace and complete the quest.
Next Main Scenario Quest
After you complete the quest, talk to U'odh Nunh to accept the next quest: When the Worm Turns.