Spawn locations (click for map image) for your "heartoffear.txt" map file (note: see this quest entry for all Heart of Fear named map points):
P -137.2040, 831.2939, 2.3034, 127, 0, 0, 1, Harbinger_Krask
P 206.0288, 1655.8677, 1.1608, 127, 0, 0, 1, Harbinger_Krask
P 150.2367, 970.3305, 0.7684, 127, 0, 0, 1, Harbinger_Krask
Known spawn locations, in-game /locs (PHs are "an enraged harbinger"):
-830, 135, 2
-1655, -205, 1
-970, -150, 0
This is a named troll.
Casts Dark Salivation (dispellable lifetap proc on itself) every 30 seconds.
Casts Icy Sludge (random single target nuke for 35,000 dmg + melee slow + snare -- 90 curse counters) 15 seconds after engage and then every 20 seconds.