diff --git a/server/gameserver/buff.cc b/server/gameserver/buff.cc
index 6ebce80..e18d367 100644
--- a/server/gameserver/buff.cc
+++ b/server/gameserver/buff.cc
@@ -18,9 +18,28 @@ Buff::Buff()
 
 }
 
-void Buff::Initialize()
+void Buff::Init()
 {
+    INIT_LIST_HEAD(&effect_entry);
+    INIT_LIST_HEAD(&depend_entry);
+    INIT_LIST_HEAD(&cond_entry);
+    INIT_LIST_HEAD(&on_remove_contexts);
+}
 
+void Buff::UnInit()
+{
+    list_del_init(&effect_entry);
+    if (!list_empty(&depend_entry)) {
+        list_del_init(&depend_entry);
+    }
+    if (!list_empty(&cond_entry)) {
+        list_del_init(&cond_entry);
+    }
+    while (!list_empty(&on_remove_contexts)) {
+        RemoveBuffCbConext* cb = list_last_entry(&on_remove_contexts, RemoveBuffCbConext, entry);
+        *cb->next = (*cb->next)->next;
+        list_del_init(&cb->entry);
+    }
 }
 
 int Buff::GetLeftTime()
diff --git a/server/gameserver/buff.h b/server/gameserver/buff.h
index 58ed6dd..bba2d62 100644
--- a/server/gameserver/buff.h
+++ b/server/gameserver/buff.h
@@ -17,6 +17,12 @@ namespace cs
     class MFBuff;
 }
 
+struct RemoveBuffCbConext
+{
+    list_head** next;
+    list_head entry;
+};
+
 class Human;
 class Creature;
 class Buff
@@ -31,9 +37,11 @@ class Buff
     list_head effect_entry;
     list_head depend_entry;
     list_head cond_entry;
+    list_head on_remove_contexts;
 
     Buff();
-    void Initialize();
+    void Init();
+    void UnInit();
     int GetLeftTime();
     int GetLastingTime();
     bool NeedSync(Human* hum);
diff --git a/server/gameserver/creature.cc b/server/gameserver/creature.cc
index 430f6d9..0158e81 100644
--- a/server/gameserver/creature.cc
+++ b/server/gameserver/creature.cc
@@ -205,15 +205,12 @@ void Creature::AddBuff(Creature* caster,
     buff->skill_meta = buff_skill_meta;
     buff->add_frameno = room->GetFrameNo();
     buff->xtimer_attacher.xtimer = &room->xtimer;
+    buff->Init();
     list_add_tail(&buff->effect_entry, &buff_effect_[buff->meta->i->buff_effect()]);
     if (buff->meta->i->depend_effect() != 0 &&
         IsValidBuffEffect(buff->meta->i->depend_effect())) {
         list_add_tail(&buff->depend_entry, &depend_effect_[buff->meta->i->depend_effect()]);
-    } else {
-        INIT_LIST_HEAD(&buff->depend_entry);
     }
-    INIT_LIST_HEAD(&buff->cond_entry);
-    buff->Initialize();
     {
         room->xtimer.AddDeadLineTimerAndAttach
             (
@@ -284,15 +281,9 @@ void Creature::RemoveBuffById(int buff_id)
     for (auto itr = buff_list_.begin(); itr != buff_list_.end(); ++itr) {
         Buff& buff = *itr;
         if (buff.meta->i->buff_id() == buff_id) {
-            list_del_init(&buff.effect_entry);
-            if (!list_empty(&buff.depend_entry)) {
-                list_del_init(&buff.depend_entry);
-            }
-            if (!list_empty(&buff.cond_entry)) {
-                list_del_init(&buff.cond_entry);
-            }
             removed_buffs.push_back(std::make_tuple(buff.meta, buff.GetCaster().Get()));
             OnBuffRemove(buff);
+            buff.UnInit();
             buff_list_.erase(itr);
             break;
         }
diff --git a/server/gameserver/creature.h b/server/gameserver/creature.h
index 9d03fef..0af24df 100644
--- a/server/gameserver/creature.h
+++ b/server/gameserver/creature.h
@@ -258,6 +258,7 @@ private:
     std::map<int, Skill*> passive_skill_hash_;
     std::array<Inventory, IS_END> inventory_ = {};
     friend class Skill;
+    friend class Trigger;
 };
 
 void InternalShot(Creature* sender,
diff --git a/server/gameserver/trigger.cc b/server/gameserver/trigger.cc
index 2904603..9d43f40 100644
--- a/server/gameserver/trigger.cc
+++ b/server/gameserver/trigger.cc
@@ -1,6 +1,9 @@
 #include "precompile.h"
 
+#include <a8/list.h>
+
 #include "trigger.h"
+#include "creature.h"
 
 void Trigger::Init()
 {
@@ -44,3 +47,32 @@ void Trigger::Die()
 {
 
 }
+
+void Trigger::TraverseCondBuffs(int cond, std::function<void (Buff*, bool&)> func)
+{
+    if (!IsValidCondBuff(cond)) {
+        abort();
+    }
+
+    list_head* pos = nullptr;
+    list_head* next = nullptr;
+    list_head* head = &owner_->cond_buffs_[cond];
+    RemoveBuffCbConext cb;
+    cb.next = &next;
+    INIT_LIST_HEAD(&cb.entry);
+    list_for_each_safe(pos, next, head) {
+        if (list_empty(next)) {
+            Buff *next_buff = list_entry(next, Buff, cond_entry);
+            list_add_tail(&cb.entry, &next_buff->on_remove_contexts);
+        }
+        Buff *curr_buff = list_entry(pos, Buff, cond_entry);
+        bool stop = false;
+        func(curr_buff, stop);
+        if (!list_empty(&cb.entry)) {
+            list_del_init(&cb.entry);
+        }
+        if (stop) {
+            return;
+        }
+    }
+}
diff --git a/server/gameserver/trigger.h b/server/gameserver/trigger.h
index 3894304..86e3f0c 100644
--- a/server/gameserver/trigger.h
+++ b/server/gameserver/trigger.h
@@ -3,6 +3,7 @@
 class Weapon;
 class Creature;
 class Skill;
+class Buff;
 class Trigger
 {
 public:
@@ -19,6 +20,9 @@ public:
     void HpChg(float old_hp, float new_hp);
     void Die();
 
+ private:
+    void TraverseCondBuffs(int cond, std::function<void (Buff*, bool&)> func);
+
  private:
     Creature* owner_ = nullptr;
 };