Schwarzen Rand? Ich nehme mal an du meinst die Schatten.
Dazu gibts dieses Call-Script-Event

Code:
for x in 0...$game_map.data.xsize
  for y in 0...$game_map.data.ysize
    #oberes belegt?
    if $game_map.data[x,y,2] == 0
      $game_map.data[x,y,2] = $game_map.data[x,y,1]
      $game_map.data[x,y,1] = $game_map.data[x,y,0]
      $game_map.data[x,y,0] = 0
    end
  end
end