diff --git a/zone/aggro.cpp b/zone/aggro.cpp
index d1574dc50..78fab6758 100644
--- a/zone/aggro.cpp
+++ b/zone/aggro.cpp
@@ -285,6 +285,14 @@ bool Mob::CheckWillAggro(Mob *mob) {
 		return(false);
 	}
 
+	// 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)))) {
+		Log.Out(Logs::Moderate, Logs::Aggro,
+			"%s is in combat, and does not have prox_aggro, or does and is out of combat range with %s",
+			GetName(), mob->GetName());
+		return false;
+	}
+
 	//im not sure I understand this..
 	//if I have an owner and it is not this mob, then I cannot
 	//aggro this mob...???
diff --git a/zone/common.h b/zone/common.h
index 0b875456b..7901d511e 100644
--- a/zone/common.h
+++ b/zone/common.h
@@ -138,7 +138,8 @@ enum {
 	IGNORE_ROOT_AGGRO_RULES = 42,
 	CASTING_RESIST_DIFF = 43,
 	COUNTER_AVOID_DAMAGE = 44,
-	MAX_SPECIAL_ATTACK = 45
+	PROX_AGGRO = 45,
+	MAX_SPECIAL_ATTACK = 46
 };
 
 typedef enum {	//fear states