Map points for "shardslanding.txt" map file (note for all Shard's Landing named map points, see this quest entry):
PH is "a frostcoat patriarch".
Every 25 seconds, casts "Stonecoat's Trap" on a random target. If, while inflicted with this, you move from your current location, the debuff immediately fades. If this happens (or if you cure it), you are hit with "Stonecoat's Vengeance". If the debuff fades naturally, "Stonecoat's Vengeance" will not damage you.