diff --git a/config/fxdata/rules.cfg b/config/fxdata/rules.cfg
index 1ed441bdbd..7dd9301444 100644
--- a/config/fxdata/rules.cfg
+++ b/config/fxdata/rules.cfg
@@ -247,3 +247,4 @@ NegSpellAll = SPELL_SLOW               VAMPIRE DEMONSPAWN
 ;MkGoodHero = AVATAR                   KNIGHT SAMURAI WIZARD GIANT MONK
 ;NegUniqFunc = COSTLIER_IMPS           TUNNELLER
 ;NegUniqFunc = ALL_CREATRS_VER_ANGRY   VAMPIRE HORNY
+;PosUniqFunc = ALL_CREATRS_HAPPY       TIME_MAGE FAIRY
diff --git a/src/config_rules.c b/src/config_rules.c
index 71770bf47f..4ba0fb6881 100644
--- a/src/config_rules.c
+++ b/src/config_rules.c
@@ -217,6 +217,7 @@ const struct NamedCommand rules_sacrifices_commands[] = {
 
 const struct NamedCommand sacrifice_unique_desc[] = {
   {"ALL_CREATRS_ANGRY",     UnqF_MkAllAngry},
+  {"ALL_CREATRS_HAPPY",     UnqF_MkAllHappy},
   {"COMPLETE_RESEARCH",     UnqF_ComplResrch},
   {"COMPLETE_MANUFACTR",    UnqF_ComplManufc},
   {"KILL_ALL_CHICKENS",     UnqF_KillChickns},
diff --git a/src/config_rules.h b/src/config_rules.h
index 953f923c43..13ea5683a6 100644
--- a/src/config_rules.h
+++ b/src/config_rules.h
@@ -52,6 +52,7 @@ enum UniqueFunctions {
     UnqF_KillChickns,
     UnqF_CheaperImp,
     UnqF_CostlierImp,
+    UnqF_MkAllHappy,
 };
 
 enum SacrificeReturn {
diff --git a/src/creature_states_pray.c b/src/creature_states_pray.c
index ffa3f4cf3c..b48dd510a5 100644
--- a/src/creature_states_pray.c
+++ b/src/creature_states_pray.c
@@ -269,6 +269,51 @@ TbBool make_all_players_creatures_angry(long plyr_idx)
     return true;
 }
 
+TbBool anger_make_creature_happy(struct Thing* creatng)
+{
+    struct CreatureStats* crstat = creature_stats_get_from_thing(creatng);
+    if ((crstat->annoy_level <= 0))
+        return false;
+    if (!anger_free_for_anger_decrease(creatng))
+    {
+        return false;
+    }
+    creature_be_happy(creatng);
+    anger_set_creature_anger_all_types(creatng, 0);
+    return true;
+}
+
+TbBool make_all_players_creatures_happy(long plyr_idx)
+{
+    SYNCDBG(8, "Starting");
+    struct Dungeon* dungeon = get_players_num_dungeon(plyr_idx);
+    unsigned long k = 0;
+    int i = dungeon->creatr_list_start;
+    while (i != 0)
+    {
+        struct Thing* thing = thing_get(i);
+        TRACE_THING(thing);
+        struct CreatureControl* cctrl = creature_control_get_from_thing(thing);
+        if (thing_is_invalid(thing) || creature_control_invalid(cctrl))
+        {
+            ERRORLOG("Jump to invalid creature detected");
+            break;
+        }
+        i = cctrl->players_next_creature_idx;
+        // Thing list loop body
+        anger_make_creature_happy(thing);
+        // Thing list loop body ends
+        k++;
+        if (k > CREATURES_COUNT)
+        {
+            ERRORLOG("Infinite loop detected when sweeping creatures list");
+            break;
+        }
+    }
+    SYNCDBG(19, "Finished");
+    return true;
+}
+
 long force_complete_current_manufacturing(long plyr_idx)
 {
     struct Dungeon* dungeon = get_players_num_dungeon(plyr_idx);
@@ -461,6 +506,9 @@ long create_sacrifice_unique_award(struct Coord3d *pos, PlayerNumber plyr_idx, l
   case UnqF_CostlierImp:
       tally_sacrificed_imps(plyr_idx, -1);
       return SacR_AngryWarn;
+  case UnqF_MkAllHappy:
+      make_all_players_creatures_happy(plyr_idx);
+      return SacR_Awarded;
   default:
       ERRORLOG("Unsupported unique sacrifice award!");
       return SacR_AngryWarn;