diff --git a/source/enemy/nshell.cpp b/source/enemy/nshell.cpp
index 6058ef385..826c73455 100644
--- a/source/enemy/nshell.cpp
+++ b/source/enemy/nshell.cpp
@@ -85,3 +85,9 @@ void CNpcShellEnemy::render()
 	}
 }
 
+////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
+
+void CNpcShellEnemy::collidedWith( CThing *_thisThing )
+{
+	// do nothing
+}
diff --git a/source/enemy/nshell.h b/source/enemy/nshell.h
index bb7d7d133..7d51bce6e 100644
--- a/source/enemy/nshell.h
+++ b/source/enemy/nshell.h
@@ -25,7 +25,9 @@ public:
 	virtual void		render();
 	virtual int			getFrameCount()							{return( 1 );}
 	virtual int			getFrame()								{return( m_shellType );}
+	virtual u8			hasBeenAttacked()						{return( false );}
 protected:
+	virtual void		collidedWith(CThing *_thisThing);
 
 	u8					m_shellType;
 };