Turn up your particles to see the black splash better
Wander around, on the ground, along the coast at ( -899, 18, -59 ) Copy/waypoint -899, 18, -59. Red text will appear: "A recluse bluffstalker is attacking you!'. Kill a recluse bluffstalker that spawns. Step slightly away from erupting sand particles and step back to this spawn spot until eruptions disappear.
Note the spawn points have black exploding sand animation
Proceed to ( -703, 12, -867 ) Copy/waypoint -703, 12, -867. Kill a recluse bluffstalker that spawns. Be aware this is close to spawn point for Tombstrike Both locations are required.
Walk or fly low to ( -955, 12, -450 ) Copy/waypoint -955, 12, -450 and kill the a great black bluffstalker that spawns.