diff --git a/battleship/utils.py b/battleship/utils.py
index 6e4b5f3..6f76c1f 100644
--- a/battleship/utils.py
+++ b/battleship/utils.py
@@ -103,7 +103,7 @@ def kill_field(field):
     for i in range(10):
         for j in range(10):
             if cells[i][j] == '+':
-                ship = set([(i, j)])
+                ship = [(i, j)]
                 queue = [(i, j)]
                 killed = True
                 while queue:
@@ -116,14 +116,14 @@ def kill_field(field):
                         elif cells[x - 1][y] == '+':
                             if (x - 1, y) not in ship:
                                 queue.append((x - 1, y))
-                                ship.add((x - 1, y))
+                                ship.append((x - 1, y))
                     if x < 9:
                         if cells[x + 1][y] == 'o':
                             killed = False
                             break
                         elif cells[x + 1][y] == '+':
                             if (x + 1, y) not in ship:
-                                ship.add((x + 1, y))
+                                ship.append((x + 1, y))
                                 queue.append((x + 1, y))
                     if y > 0:
                         if cells[x][y - 1] == 'o':
@@ -131,7 +131,7 @@ def kill_field(field):
                             break
                         elif cells[x][y - 1] == '+':
                             if (x, y - 1) not in ship:
-                                ship.add((x, y - 1))
+                                ship.append((x, y - 1))
                                 queue.append((x, y - 1))
                     if y < 9:
                         if cells[x][y + 1] == 'o':
@@ -139,9 +139,11 @@ def kill_field(field):
                             break
                         elif cells[x][y + 1] == '+':
                             if (x, y + 1) not in ship:
-                                ship.add((x, y + 1))
+                                ship.append((x, y + 1))
                                 queue.append((x, y + 1))
                 if killed:
                     for x, y in ship:
                         cells[x][y] = 'x'
+                    for x, y in find_borders(ship[0][0], ship[0][1], len(ship), not bool(ship[-1][1] - ship[0][1])):
+                        cells[x][y] = '.'
     return ''.join([''.join(arr) for arr in cells])