diff --git a/server/gameserver/hero.ai.cc b/server/gameserver/hero.ai.cc
index fb67c2cf..f31ecc7c 100644
--- a/server/gameserver/hero.ai.cc
+++ b/server/gameserver/hero.ai.cc
@@ -582,7 +582,8 @@ RoomObstacle* HeroAI::FindObstacleTarget()
         myself->room->xtimer.AddDeadLineTimerAndAttach
             (
              SERVER_FRAME_RATE * 2,
-             a8::XParams(),
+             a8::XParams()
+             .SetSender(target),
              [] (const a8::XParams& param)
              {
                  RoomObstacle* obstacle = (RoomObstacle*)param.sender.GetUserData();