diff --git a/zone/aggro.cpp b/zone/aggro.cpp
index 4d020ce3d..0de43c3ca 100644
--- a/zone/aggro.cpp
+++ b/zone/aggro.cpp
@@ -456,7 +456,12 @@ bool Mob::CheckWillAggro(Mob *mob) {
 	}
 
 	// Don't aggro new clients if we are already engaged unless PROX_AGGRO is set
-	if (IsEngaged() && (!GetSpecialAbility(PROX_AGGRO) || (GetSpecialAbility(PROX_AGGRO) && !CombatRange(mob)))) {
+
+	// Frustrated mobs (all rooted up with no one to kill)
+	// will engage without PROX_AGGRO ability if someone new is close now.
+	bool is_frustrated = (IsRooted() && !CombatRange(target));
+
+	if (!is_frustrated && IsEngaged() && (!GetSpecialAbility(PROX_AGGRO) || (GetSpecialAbility(PROX_AGGRO) && !CombatRange(mob)))) {
 		LogAggro(
 			"[{}] is in combat, and does not have prox_aggro, or does and is out of combat range with [{}]",
 			GetName(),