diff --git a/server/gameserver/buff/bufffactory.cc b/server/gameserver/buff/bufffactory.cc
index 30e80708..e94f29f4 100644
--- a/server/gameserver/buff/bufffactory.cc
+++ b/server/gameserver/buff/bufffactory.cc
@@ -44,6 +44,7 @@
 #include "buff/vertigo.h"
 #include "buff/cond_add.h"
 #include "buff/distance_dmg_addition.h"
+#include "buff/downed.h"
 
 #include "mt/Buff.h"
 
@@ -128,6 +129,8 @@ std::shared_ptr<Buff> BuffFactory::MakeBuff(const mt::Buff* buff_meta)
         return std::make_shared<VertigoBuff>();
     case kBET_CondAdd:
         return std::make_shared<CondAddBuff>();
+    case kBET_Down:
+        return std::make_shared<DownedBuff>();
     default:
         return std::make_shared<Buff>();
     }
diff --git a/server/gameserver/buff/downed.cc b/server/gameserver/buff/downed.cc
new file mode 100644
index 00000000..72905890
--- /dev/null
+++ b/server/gameserver/buff/downed.cc
@@ -0,0 +1,27 @@
+#include "precompile.h"
+
+#include "buff/downed.h"
+
+#include "creature.h"
+#include "human.h"
+#include "room.h"
+
+#include "mt/Buff.h"
+
+void DownedBuff::Activate()
+{
+    if (!owner->room->IsDestorying() && !owner->room->IsGameOver()) {
+        if (owner->IsHuman()) {
+            owner->AsHuman()->SendViewerUiMemberUpdate({owner->GetUniId()});
+        }
+    }
+}
+
+void DownedBuff::Deactivate()
+{
+    if (!owner->room->IsDestorying() && !owner->room->IsGameOver()) {
+        if (owner->IsHuman()) {
+            owner->AsHuman()->SendViewerUiMemberUpdate({owner->GetUniId()});
+        }
+    }
+}
diff --git a/server/gameserver/buff/downed.h b/server/gameserver/buff/downed.h
new file mode 100644
index 00000000..37935415
--- /dev/null
+++ b/server/gameserver/buff/downed.h
@@ -0,0 +1,12 @@
+#pragma once
+
+#include "buff.h"
+
+class DownedBuff : public Buff
+{
+ public:
+
+    virtual void Activate() override;
+    virtual void Deactivate() override;
+
+};
diff --git a/server/gameserver/human.cc b/server/gameserver/human.cc
index 214d8d5b..67eb907b 100644
--- a/server/gameserver/human.cc
+++ b/server/gameserver/human.cc
@@ -3535,6 +3535,7 @@ void Human::InternalBeKill(int killer_id, const std::string& killer_name, int we
             }
         }
     }
+    SendViewerUiMemberUpdate({GetUniId(), killer_id, real_killer_id});
 }
 
 int Human::GetTeamMode()
diff --git a/server/gameserver/pbutils.cc b/server/gameserver/pbutils.cc
index 0aa17244..056ae148 100644
--- a/server/gameserver/pbutils.cc
+++ b/server/gameserver/pbutils.cc
@@ -1720,27 +1720,6 @@ void Human::SendUIUpdate()
         notifymsg.set_boss_state(room->pve_data.boss_state);
     }
     if (room->IsMobaModeRoom()) {
-#if 0
-        if (GetTeam()->GetTeamId() == room->GetMobaTeamA()->GetTeamId()) {
-            if (room->GetMobaTeamA()) {
-                notifymsg.set_a_team_id(room->GetMobaTeamB()->GetTeamId());
-                notifymsg.set_a_kill_count(room->GetMobaTeamB()->GetKillCount());
-            }
-            if (room->GetMobaTeamB()) {
-                notifymsg.set_b_team_id(room->GetMobaTeamA()->GetTeamId());
-                notifymsg.set_b_kill_count(room->GetMobaTeamA()->GetKillCount());
-            }
-        } else {
-            if (room->GetMobaTeamA()) {
-                notifymsg.set_a_team_id(room->GetMobaTeamA()->GetTeamId());
-                notifymsg.set_a_kill_count(room->GetMobaTeamA()->GetKillCount());
-            }
-            if (room->GetMobaTeamB()) {
-                notifymsg.set_b_team_id(room->GetMobaTeamB()->GetTeamId());
-                notifymsg.set_b_kill_count(room->GetMobaTeamB()->GetKillCount());
-            }
-        }
-#else
         if (room->GetMobaTeamA()) {
             notifymsg.set_a_team_id(room->GetMobaTeamA()->GetTeamId());
             notifymsg.set_a_kill_count(room->GetMobaTeamA()->GetKillCount());
@@ -1749,8 +1728,7 @@ void Human::SendUIUpdate()
             notifymsg.set_b_team_id(room->GetMobaTeamB()->GetTeamId());
             notifymsg.set_b_kill_count(room->GetMobaTeamB()->GetKillCount());
         }
-#endif
-#ifdef MYDEBUG1
+#ifdef MYDEBUG
         a8::XPrintf("zzzzzzzzzzzzz self_team_id:%d data:%s\n",
                     {
                      GetTeam()->GetTeamId(),
@@ -2279,33 +2257,40 @@ void Human::SendViewerUiNotify()
              return true;
          });
 #ifdef MYDEBUG
-    a8::XPrintf("SMViewerUiNotify %s", {f8::PbToJson(&msg)});
+    a8::XPrintf("SMViewerUiNotify %d %s\n", {socket_handle, f8::PbToJson(&msg)});
 #endif
     SendNotifyMsg(msg);
 }
 
 void Human::SendViewerUiMemberUpdate(std::vector<int> member_ids)
 {
-    if (!IsOb()) {
-        return;
-    }
-    cs::SMViewerUiMemberUpdate msg;
-    for (int id : member_ids) {
-        Player* hum = room->GetPlayerByUniId(id);
-        if (hum) {
-            auto m = msg.add_members();
-            m->set_team_id(hum->GetTeam()->GetTeamId());
-            m->set_member_uniid(hum->GetUniId());
-            m->set_name(hum->GetName());
-            m->set_avatar_url(hum->avatar_url);
-            m->set_hero_id(hum->meta->id());
-            m->set_head_frame(hum->head_frame);
-            m->set_kills(hum->stats->kills);
-            m->set_dead(hum->dead);
-            m->set_downed(hum->downed);
+    if (room->GetRoomOb()->HasOb()) {
+        cs::SMViewerUiMemberUpdate msg;
+        for (int id : member_ids) {
+            Human* hum = room->GetHumanByUniId(id);
+            if (hum) {
+                auto m = msg.add_members();
+                m->set_team_id(hum->GetTeam()->GetTeamId());
+                m->set_member_uniid(hum->GetUniId());
+                m->set_name(hum->GetName());
+                m->set_avatar_url(hum->avatar_url);
+                m->set_hero_id(hum->meta->id());
+                m->set_head_frame(hum->head_frame);
+                m->set_kills(hum->stats->kills);
+                m->set_dead(hum->dead);
+                m->set_downed(hum->downed);
+            }
         }
+        room->GetRoomOb()->TraverseOb
+            (
+             [&msg] (Player* ele_hum) -> bool
+             {
+#ifdef MYDEBUG
+                 a8::XPrintf("SMViewerUiMemberNotify %d %s\n", {ele_hum->socket_handle, f8::PbToJson(&msg)});
+#endif
+                 ele_hum->SendNotifyMsg(msg);
+             });
     }
-    SendNotifyMsg(msg);
 }
 
 void GGListener::SendError(int sockhandle, unsigned int seqid,
diff --git a/server/gameserver/roomob.h b/server/gameserver/roomob.h
index a492b050..e48d6365 100644
--- a/server/gameserver/roomob.h
+++ b/server/gameserver/roomob.h
@@ -15,6 +15,7 @@ class RoomOb : public std::enable_shared_from_this<RoomOb>
     Player* GetByAccountId(const std::string& account_id);
     void AddOb(Player* hum);
     void TraverseOb(std::function<bool (Player*)> cb);
+    bool HasOb() { return !id_hash_.empty(); }
 
 private:
     Room* room_ = nullptr;