Talk to Lahrian to discover his predicament and how you can help.
The 'hardest' part of this scavenger hunt tends to be the Wild Boar tusks. The best option is to travel to the Western Tyr Lysia portal and then head back south until you have collected enough. If you do not have that portal active, head north along the road until you collect enough and then head back.
Kobold Stone Throwers drop the hearts you need - you can find plenty near the Golden Coast Resurrection Monument, or on the trail to the Forgotten Gardens/Seraphim Valley.
Plenty of Small Earth Elementals can also be found in the Seraphim Valley. You can also find them east of Lahrian's house along the beach.
As soon as you have all of your ingredients return to Lahrian to complete the quest.
- Although you have to complete the quest Lahrian is Missing in order to access this quest, the two quests are not part of a chain (according to the quest log).