diff --git a/conf/battle/monster.conf b/conf/battle/monster.conf
index 78a4fb2d60..012bb622bd 100644
--- a/conf/battle/monster.conf
+++ b/conf/battle/monster.conf
@@ -269,8 +269,10 @@ monster_stuck_warning: no
 // On small-medium sized servers this can cause all monsters like eggs and Fabre/Pupa to metamorph.
 // To switch it off, set it to 0.
 mob_nopc_idleskill_rate: 100
+boss_nopc_idleskill_rate: 100
 
 // Rate at which monsters move when there are no players nearby (Note 2)
 // On official servers monsters always move if they have been spotted once, even if there are no players nearby anymore.
 // To switch it off, set it to 0.
 mob_nopc_move_rate: 100
+boss_nopc_move_rate: 100
diff --git a/src/map/battle.cpp b/src/map/battle.cpp
index 03b44ca80b..f73495f53d 100644
--- a/src/map/battle.cpp
+++ b/src/map/battle.cpp
@@ -8557,8 +8557,10 @@ static const struct _battle_data {
 	{ "feature.equipswitch",                &battle_config.feature_equipswitch,             1,      0,      1,              },
 	{ "pet_walk_speed",                     &battle_config.pet_walk_speed,                  1,      1,      3,              },
 	{ "blacksmith_fame_refine_threshold",   &battle_config.blacksmith_fame_refine_threshold,10,     1,      MAX_REFINE,     },
-	{ "mob_nopc_idleskill_rate",            &battle_config.mob_nopc_idleskill_rate,       100,      0,    100,              },
-	{ "mob_nopc_move_rate",                 &battle_config.mob_nopc_move_rate,            100,      0,    100,              },
+	{ "mob_nopc_idleskill_rate",            &battle_config.mob_nopc_idleskill_rate,         100,    0,    100,              },
+	{ "mob_nopc_move_rate",                 &battle_config.mob_nopc_move_rate,              100,    0,    100,              },
+	{ "boss_nopc_idleskill_rate",           &battle_config.boss_nopc_idleskill_rate,        100,    0,    100,              },
+	{ "boss_nopc_move_rate",                &battle_config.boss_nopc_move_rate,             100,    0,    100,              },
 
 #include "../custom/battle_config_init.inc"
 };
diff --git a/src/map/battle.hpp b/src/map/battle.hpp
index 3fd0b794ff..e53b07d2ff 100644
--- a/src/map/battle.hpp
+++ b/src/map/battle.hpp
@@ -661,6 +661,8 @@ struct Battle_Config
 	int blacksmith_fame_refine_threshold;
 	int mob_nopc_idleskill_rate;
 	int mob_nopc_move_rate;
+	int boss_nopc_idleskill_rate;
+	int boss_nopc_move_rate;
 
 #include "../custom/battle_config_struct.inc"
 };
diff --git a/src/map/mob.cpp b/src/map/mob.cpp
index b1258fb2c6..9120b17d83 100644
--- a/src/map/mob.cpp
+++ b/src/map/mob.cpp
@@ -2048,7 +2048,9 @@ static int mob_ai_sub_lazy(struct mob_data *md, va_list args)
 	{
 		// Move probability for mobs away from players
 		// In Aegis, this is 100% for mobs that have been activated by players and none otherwise.
-		if( mob_is_spotted(md) && rnd()%100 < battle_config.mob_nopc_move_rate )
+		if( mob_is_spotted(md) &&
+			((!status_has_mode(&md->status,MD_STATUS_IMMUNE) && rnd()%100 < battle_config.mob_nopc_move_rate) ||
+			(status_has_mode(&md->status,MD_STATUS_IMMUNE) && rnd()%100 < battle_config.boss_nopc_move_rate)))
 			mob_randomwalk(md, tick);
 	}
 	else if( md->ud.walktimer == INVALID_TIMER )
@@ -2058,7 +2060,9 @@ static int mob_ai_sub_lazy(struct mob_data *md, va_list args)
 
 		// Probability for mobs far from players from doing their IDLE skill.
 		// In Aegis, this is 100% for mobs that have been activated by players and none otherwise.
-		if( mob_is_spotted(md) && rnd()%100 < battle_config.mob_nopc_idleskill_rate )
+		if( mob_is_spotted(md) &&
+			((!status_has_mode(&md->status,MD_STATUS_IMMUNE) && rnd()%100 < battle_config.mob_nopc_idleskill_rate) ||
+			(status_has_mode(&md->status,MD_STATUS_IMMUNE) && rnd()%100 < battle_config.boss_nopc_idleskill_rate)))
 			mobskill_use(md, tick, -1);
 	}