Investigate the Lair of Acanthus is the 3rd mission unlocked in the Deathbringer tier of missions at level 58.

This mission requires 33 energy as well as 15 Invisibility and 15 Shadow Manipulation abilities. Also, this mission requires 1 Charon's Obol and 5 Pentagram Shard at Mastery levels 2 and 3.

On completion, it provides between 1,600,000 and 3,000,000 blood and 42 experience points. Completing the mission will sometimes provide a mission item, Map Fragment.

Each time the mission is completed, mission mastery increases by 7% for Mastery Level 1, 6% for Mastery Level 2, and 5% for Mastery Level 3.