hidden wards in walls

in the top portion of the map the red buff directly south of the minion that's to the right of the large monster if you place a ward through the wall as in selecting the wall itself it will get wedged partially into the terrain to the point that 1/4 or a quarter of it is invisible and (ive only succeeded in this once) if it is properly placed it ignores walls and grants vision in a large radius as if there were no walls obstructing its view the ward i was using was the death ward