diff --git a/backend/internal/handler/npc.go b/backend/internal/handler/npc.go
index b87b51b..2de11b0 100644
--- a/backend/internal/handler/npc.go
+++ b/backend/internal/handler/npc.go
@@ -169,9 +169,14 @@ func (h *NPCHandler) InteractNPC(w http.ResponseWriter, r *http.Request) {
 
 	switch npc.Type {
 	case "quest_giver":
-		daySeed := time.Now().UTC().Unix() / 86400
+		refreshHours := tuning.EffectiveQuestOfferRefreshHours()
+		if refreshHours <= 0 {
+			refreshHours = 2
+		}
+		refreshSeconds := int64(time.Duration(refreshHours) * time.Hour / time.Second)
+		timeBucket := time.Now().UTC().Unix() / refreshSeconds
 		limit := tuning.EffectiveQuestOffersPerNPC()
-		quests, err := h.questStore.ListOfferableQuestsForNPC(r.Context(), hero.ID, npc.ID, hero.Level, limit, daySeed)
+		quests, err := h.questStore.ListOfferableQuestsForNPC(r.Context(), hero.ID, npc.ID, hero.Level, limit, timeBucket)
 		if err != nil {
 			h.logger.Error("failed to list quests for npc interaction", "npc_id", npc.ID, "error", err)
 			writeJSON(w, http.StatusInternalServerError, map[string]string{
diff --git a/backend/internal/handler/quest.go b/backend/internal/handler/quest.go
index d98841e..6d0ef8b 100644
--- a/backend/internal/handler/quest.go
+++ b/backend/internal/handler/quest.go
@@ -121,7 +121,7 @@ func (h *QuestHandler) ListBuildingsByTown(w http.ResponseWriter, r *http.Reques
 
 // ListQuestsByNPC returns quests offered by an NPC.
 // GET /api/v1/npcs/{npcId}/quests
-// With ?telegramId= the list is filtered (no already-logged templates), level-scoped, capped, and rotated daily — same rules as npc-interact.
+// With ?telegramId= the list is filtered (no already-logged templates), level-scoped, capped, and rotated on a configured cadence — same rules as npc-interact.
 // Without telegramId, returns all templates for that NPC (catalog / tools).
 func (h *QuestHandler) ListQuestsByNPC(w http.ResponseWriter, r *http.Request) {
 	npcIDStr := chi.URLParam(r, "npcId")
@@ -155,9 +155,14 @@ func (h *QuestHandler) ListQuestsByNPC(w http.ResponseWriter, r *http.Request) {
 			})
 			return
 		}
-		daySeed := time.Now().UTC().Unix() / 86400
+		refreshHours := tuning.EffectiveQuestOfferRefreshHours()
+		if refreshHours <= 0 {
+			refreshHours = 2
+		}
+		refreshSeconds := int64(time.Duration(refreshHours) * time.Hour / time.Second)
+		timeBucket := time.Now().UTC().Unix() / refreshSeconds
 		limit := tuning.EffectiveQuestOffersPerNPC()
-		quests, err := h.questStore.ListOfferableQuestsForNPC(r.Context(), hero.ID, npcID, hero.Level, limit, daySeed)
+		quests, err := h.questStore.ListOfferableQuestsForNPC(r.Context(), hero.ID, npcID, hero.Level, limit, timeBucket)
 		if err != nil {
 			h.logger.Error("failed to list offerable quests", "npc_id", npcID, "error", err)
 			writeJSON(w, http.StatusInternalServerError, map[string]string{
diff --git a/backend/internal/storage/quest_store.go b/backend/internal/storage/quest_store.go
index ba1de6c..7fc06cb 100644
--- a/backend/internal/storage/quest_store.go
+++ b/backend/internal/storage/quest_store.go
@@ -261,8 +261,8 @@ func (s *QuestStore) HeroTakenQuestTemplateIDs(ctx context.Context, heroID int64
 }
 
 // ListOfferableQuestsForNPC returns level-matching NPC quests excluding templates already on the hero's log.
-// limit comes from tuning (e.g. questOffersPerNPC). daySeed should be UTC day bucket (e.g. unix/86400) for daily rotation.
-func (s *QuestStore) ListOfferableQuestsForNPC(ctx context.Context, heroID, npcID int64, heroLevel int, limit int, daySeed int64) ([]model.Quest, error) {
+// limit comes from tuning (e.g. questOffersPerNPC). timeBucket is a stable bucket (e.g. unixSeconds/7200) for rotations.
+func (s *QuestStore) ListOfferableQuestsForNPC(ctx context.Context, heroID, npcID int64, heroLevel int, limit int, timeBucket int64) ([]model.Quest, error) {
 	all, err := s.ListQuestsByNPCForHeroLevel(ctx, npcID, heroLevel)
 	if err != nil {
 		return nil, err
@@ -275,7 +275,7 @@ func (s *QuestStore) ListOfferableQuestsForNPC(ctx context.Context, heroID, npcI
 	for _, id := range takenIDs {
 		taken[id] = struct{}{}
 	}
-	seed := heroID ^ npcID ^ daySeed
+	seed := npcID ^ timeBucket
 	return FilterCapOfferableQuests(all, taken, limit, seed), nil
 }
 
diff --git a/backend/internal/tuning/runtime.go b/backend/internal/tuning/runtime.go
index 2c5fb06..d37b61c 100644
--- a/backend/internal/tuning/runtime.go
+++ b/backend/internal/tuning/runtime.go
@@ -83,6 +83,8 @@ type Values struct {
 	NPCCostNearbyRadius     float64 `json:"npcCostNearbyRadius"`
 	// QuestOffersPerNPC caps how many quest templates a quest_giver offers per interaction (after filtering taken quests).
 	QuestOffersPerNPC int `json:"questOffersPerNPC"`
+	// QuestOfferRefreshHours controls how often quest_giver offers rotate (hours).
+	QuestOfferRefreshHours int `json:"questOfferRefreshHours"`
 
 	CombatDamageScale      float64 `json:"combatDamageScale"`
 	CombatDamageRollMin   float64 `json:"combatDamageRollMin"`
@@ -276,6 +278,7 @@ func DefaultValues() Values {
 		NPCCostPotion:                    50,
 		NPCCostNearbyRadius:              3.0,
 		QuestOffersPerNPC:                2,
+		QuestOfferRefreshHours:           2,
 		CombatDamageScale:                0.35,
 		CombatDamageRollMin:              0.60,
 		CombatDamageRollMax:              1.10,
@@ -412,6 +415,15 @@ func EffectiveQuestOffersPerNPC() int {
 	return n
 }
 
+// EffectiveQuestOfferRefreshHours returns the rotation cadence (hours) for quest_giver offers.
+func EffectiveQuestOfferRefreshHours() int {
+	n := Get().QuestOfferRefreshHours
+	if n <= 0 {
+		return DefaultValues().QuestOfferRefreshHours
+	}
+	return n
+}
+
 func Set(v Values) {
 	current.Store(&v)
 }