diff --git a/resources/graphics/moat/moat_corner_ne.png b/resources/graphics/moat/moat_corner_north_flip.png
similarity index 100%
rename from resources/graphics/moat/moat_corner_ne.png
rename to resources/graphics/moat/moat_corner_north_flip.png
diff --git a/resources/graphics/moat/moat_corner_se.png b/resources/graphics/moat/moat_corner_south_flip.png
similarity index 100%
rename from resources/graphics/moat/moat_corner_se.png
rename to resources/graphics/moat/moat_corner_south_flip.png
diff --git a/robotgame/boulder.py b/robotgame/boulder.py
index 80b4e9d..6cff2d3 100644
--- a/robotgame/boulder.py
+++ b/robotgame/boulder.py
@@ -28,6 +28,7 @@ import pygame
 
 import worldobject
 import block
+import player
 
 class Boulder(worldobject.WorldObject):
     def __init__(self, level, x, y, direction=(1, 0),
@@ -40,6 +41,8 @@ class Boulder(worldobject.WorldObject):
         self.frame = 0
         self.anim_speed = 60
 
+        self.ignore_list.append(player.Player)
+
     def activate(self, setting):
         self.rolling = True
 
diff --git a/robotgame/level1.py b/robotgame/level1.py
index 46f26ed..d040128 100644
--- a/robotgame/level1.py
+++ b/robotgame/level1.py
@@ -273,6 +273,8 @@ class Level1(level.Level):
 
         moat_list = ['moat_corner_north',
                      'moat_corner_south',
+                     'moat_corner_north_flip',
+                     'moat_corner_south_flip',
                      'moat_end_horizontal',
                      'moat_horizontal',
                      'moat_vertical']
@@ -281,10 +283,6 @@ class Level1(level.Level):
                     self.graphics_dir, 'moat', '%s.png' % moat))
 
         # Special treatment
-        self.imgs['moat_corner_north_flip'] = pygame.transform.flip(
-            self.imgs['moat_corner_north'], 1, 0)
-        self.imgs['moat_corner_south_flip'] = pygame.transform.flip(
-            self.imgs['moat_corner_south'], 1, 0)
         self.imgs['moat_end_horizontal_flip'] = pygame.transform.flip(
             self.imgs['moat_end_horizontal'], 1, 0)
 
diff --git a/robotgame/player.py b/robotgame/player.py
index bd97c5d..a0e9271 100644
--- a/robotgame/player.py
+++ b/robotgame/player.py
@@ -29,6 +29,7 @@ import re
 import os
 
 import worldobject
+import boulder
 
 class Player(worldobject.WorldObject):
     def __init__(self, level, x, y, z=1, movable=True):
@@ -41,6 +42,8 @@ class Player(worldobject.WorldObject):
         self.frame = 0
         self.anim_speed = 15
 
+        self.ignore_list.append(boulder.Boulder)
+
         self.load()
 
     def load(self):
diff --git a/robotgame/worldobject.py b/robotgame/worldobject.py
index d9e3cc2..cc178ff 100644
--- a/robotgame/worldobject.py
+++ b/robotgame/worldobject.py
@@ -41,6 +41,8 @@ class WorldObject(object):
         self.holding = None
         self.holder = None
 
+        self.ignore_list = []
+
         self.is_currently_opaque = True
 
         if hasattr(self, 'img'):
@@ -73,7 +75,8 @@ class WorldObject(object):
                 if (obj.x == self.x + move_x * self.tile_x
                     and obj.y == self.y + move_y * self.tile_y
                     and obj is not self and obj is not self.holder
-                    and obj is not self.holding and obj.blocking):
+                    and obj is not self.holding and obj.blocking
+                    and type(obj) not in self.ignore_list):
                     return False
             return True
         return False