diff --git a/server/gameserver/car.cc b/server/gameserver/car.cc
index 569e86d..9b2b398 100644
--- a/server/gameserver/car.cc
+++ b/server/gameserver/car.cc
@@ -178,3 +178,9 @@ void Car::SyncPos()
         room->grid_service->MoveCreature(this);
     }
 }
+
+float Car::GetRadius()
+{
+    abort();
+    return 0;
+}
diff --git a/server/gameserver/car.h b/server/gameserver/car.h
index 1feacd8..870d646 100644
--- a/server/gameserver/car.h
+++ b/server/gameserver/car.h
@@ -28,6 +28,7 @@ class Car : public Creature
     void GetDown(Human* passenger);
     void GetOn(Human* passenger);
     void SyncPos();
+    virtual float GetRadius() override;
 
  private:
     int AllocSeat();
diff --git a/server/gameserver/creature.cc b/server/gameserver/creature.cc
index d380785..fc744a0 100644
--- a/server/gameserver/creature.cc
+++ b/server/gameserver/creature.cc
@@ -1344,3 +1344,53 @@ RoomObstacle* Creature::SummonObstacle(int id, const a8::Vec2& pos)
     }
     return obstacle;
 }
+
+bool Creature::CollisonDetection()
+{
+    #if 0
+    if (room->OverBorder(GetPos(), GetRadius())){
+        return true;
+    }
+    if (HasBuffEffect(kBET_ThroughWall) ||
+        HasBuffEffect(kBET_Fly)) {
+        return false;
+    }
+
+    std::set<ColliderComponent*> colliders;
+    room->map_service->GetColliders(room, GetX(), GetY(), colliders);
+
+    AabbCollider aabb_box;
+    GetAabbBox(aabb_box);
+    for (ColliderComponent* collider : colliders) {
+        switch (collider->owner->GetEntityType()) {
+        case ET_Obstacle:
+            {
+                Obstacle* obstacle = (Obstacle*)collider->owner;
+                if (!obstacle->IsDead(room) &&
+                    (
+                     (collider->type == CT_Aabb && aabb_box.Intersect((ColliderComponent*)collider)) ||
+                     (collider->type == CT_Circle && self_collider_->Intersect((ColliderComponent*)collider))
+                     )) {
+                    return true;
+                }
+            }
+            break;
+        case ET_Building:
+            {
+                if (
+                    (
+                     (collider->type == CT_Aabb && aabb_box.Intersect((ColliderComponent*)collider)) ||
+                     (collider->type == CT_Circle && self_collider_->Intersect((ColliderComponent*)collider))
+                     )
+                    ) {
+                    return true;
+                }
+            }
+            break;
+        default:
+            break;
+        }
+    }
+    #endif
+    return false;
+}
diff --git a/server/gameserver/creature.h b/server/gameserver/creature.h
index 4194389..737ba02 100644
--- a/server/gameserver/creature.h
+++ b/server/gameserver/creature.h
@@ -120,6 +120,7 @@ class Creature : public MoveableEntity
 
     void CheckSpecObject();
     RoomObstacle* SummonObstacle(int id, const a8::Vec2& pos);
+    bool CollisonDetection();
 
 private:
 
diff --git a/server/gameserver/entity.h b/server/gameserver/entity.h
index fbe4b2a..fe20379 100644
--- a/server/gameserver/entity.h
+++ b/server/gameserver/entity.h
@@ -22,6 +22,7 @@ class Entity
     virtual void FillMFObjectFull(Room* room, Human* hum, cs::MFObjectFull* full_data) {};
     virtual float GetSpeed() { return 1.0f;};
     virtual void GetAabbBox(AabbCollider& aabb_box);
+    virtual float GetRadius() { return 0;};
     virtual void GetCircleBox(CircleCollider& circle_box);
     virtual bool IsDead(Room* room) { return false;};
     virtual long long GetDeadFrameNo(Room* room) { return 0;};
diff --git a/server/gameserver/hero.cc b/server/gameserver/hero.cc
index 073eefd..e246307 100644
--- a/server/gameserver/hero.cc
+++ b/server/gameserver/hero.cc
@@ -187,3 +187,9 @@ void Hero::RecalcSelfCollider()
     self_collider_->pos = a8::Vec2();
     self_collider_->rad = meta->i->radius();
 }
+
+
+float Hero::GetRadius()
+{
+    return meta->i->radius();
+}
diff --git a/server/gameserver/hero.h b/server/gameserver/hero.h
index 5cf661a..b6c4a48 100644
--- a/server/gameserver/hero.h
+++ b/server/gameserver/hero.h
@@ -30,6 +30,7 @@ public:
     virtual void GetAabbBox(AabbCollider& aabb_box) override;
 
     virtual float GetSpeed() override;
+    virtual float GetRadius() override;
 
 protected:
     virtual void _UpdateMove(int speed) override;
diff --git a/server/gameserver/human.cc b/server/gameserver/human.cc
index c9414a4..6adffcc 100644
--- a/server/gameserver/human.cc
+++ b/server/gameserver/human.cc
@@ -629,11 +629,6 @@ void Human::FindPathInMapService()
     SetPos(old_pos);
 }
 
-float Human::GetRadius()
-{
-    return meta->i->radius();
-}
-
 float Human::GetHP()
 {
     return ability.hp;
@@ -3368,3 +3363,8 @@ void Human::DoSkillPostProc(bool used, int skill_id, int target_id, const a8::Ve
         OnAttack();
     }
 }
+
+float Human::GetRadius()
+{
+    return meta->i->radius();
+}
diff --git a/server/gameserver/human.h b/server/gameserver/human.h
index 4eca4bf..7b0e8ba 100644
--- a/server/gameserver/human.h
+++ b/server/gameserver/human.h
@@ -153,7 +153,6 @@ class Human : public Creature
     virtual void RecalcSelfCollider() override;
     bool IsCollisionInMapService();
     void FindPathInMapService();
-    float GetRadius();
     float GetHP();
     float GetMaxHP();
     void BeKill(int killer_id, const std::string& killer_name, int weapon_id);
@@ -239,6 +238,7 @@ class Human : public Creature
     void SetSeat(int seat) { seat_ = seat; }
     void DeadDrop();
     virtual std::string GetName() override { return name;};
+    virtual float GetRadius() override;
 
 protected:
     void _InternalUpdateMove(float speed);
diff --git a/server/tools/protobuild/metatable.proto b/server/tools/protobuild/metatable.proto
index 3b7c6ff..6e30e28 100755
--- a/server/tools/protobuild/metatable.proto
+++ b/server/tools/protobuild/metatable.proto
@@ -146,6 +146,7 @@ message Player
     optional int32 revive_time = 22;
     optional string name = 23;
     optional int32 normal_skill = 24;
+    optional float hit_radius = 25;
 }
 
 message Robot