diff --git a/game/world_tools.py b/game/world_tools.py
index fc7022e..43a5a20 100644
--- a/game/world_tools.py
+++ b/game/world_tools.py
@@ -12,27 +12,26 @@ from tcod.map import Map
 from game.components import Gold, Graphic, Position
 from game.tags import IsActor, IsItem, IsPlayer, IsDoor
 
-def add_wall(pos, remove=False):
+def add_wall(world, pos, remove=False):
     r_pos = g.world_center + pos
-    map = g.world[None].components[Map]
+    map = world[None].components[Map]
     map.walkable[r_pos.y][r_pos.x] = remove
     map.transparent[r_pos.y][r_pos.x] = remove
 
-def add_door(pos):
-    g.world.new_entity(
+def add_door(world, pos):
+    world.new_entity(
         components={
             Position: pos,
             Graphic: Graphic(ord('\\'))
         },
         tags=[IsDoor]
     )
-    add_wall(pos)
+    add_wall(world, pos)
 
 
 def new_world() -> Registry:
     """Return a freshly generated world."""
     world = Registry()
-    g.world = world
 
     map = world[None].components[Map] = Map(100, 100)
     map.walkable[:] = True
@@ -66,9 +65,9 @@ def new_world() -> Registry:
 
     for i in range(20):
         if i == 5 or i == 9:
-            add_door(Position(10,i))
+            add_door(world, Position(10,i))
         else:
-            add_wall(Position(10, i))
+            add_wall(world, Position(10, i))
 
     return world
 
@@ -76,4 +75,4 @@ def new_world() -> Registry:
 def unlock_door(door: Entity):
     door.components[Graphic] = Graphic(ord("_"))
     door.tags.clear()
-    add_wall(door.components[Position], remove=True)
+    add_wall(g.world, door.components[Position], remove=True)