This achievement is gained upon completing all Hunter achievements.
Novice Hunter of Alaris - https://everquest.allakhazam.com/db/quest.html?quest=5810
Adept Hunter of Alaris - https://everquest.allakhazam.com/db/quest.html?quest=5811
Veteran Hunter of Alaris - https://everquest.allakhazam.com/db/quest.html?quest=5798
Expert Hunter of Alaris - https://everquest.allakhazam.com/db/quest.html?quest=5797
Rewards
Satchel of the Veilslayer - https://everquest.allakhazam.com/db/item.html?item=98698
Player flags - Title of "the Veilslayer"