diff --git a/project_constants.py b/project_constants.py
index 4c62b9c..232efa8 100644
--- a/project_constants.py
+++ b/project_constants.py
@@ -72,8 +72,8 @@ class Coords(Enum):
 
 class Terrain(Enum):
     CONCRETE = 2
-    GRASS = 10
-    MUD = 20
+    GRASS = 5
+    MUD = 8
 
 
 # =============== #
diff --git a/resources/minefields/fourthmap.json b/resources/minefields/fourthmap.json
index 6fb4e11..6bcec3c 100644
--- a/resources/minefields/fourthmap.json
+++ b/resources/minefields/fourthmap.json
@@ -173,7 +173,7 @@
       "mine": null
     },
     "3,5": {
-      "terrain": "MUD",
+      "terrain": "GRASS",
       "mine": null
     },
     "3,6": {
diff --git a/searching_algorithms/a_star.py b/searching_algorithms/a_star.py
index 2925330..c87ed90 100644
--- a/searching_algorithms/a_star.py
+++ b/searching_algorithms/a_star.py
@@ -152,7 +152,7 @@ def graphsearch(initial_state: State,
                 fringe_states.add((new_node.state.row, new_node.state.column, new_node.state.direction))
 
             # update weight if it's lower
-            elif successor_state in fringe and entry_finder[successor_state][0] > priority:
+            elif successor_state in fringe_states and entry_finder[successor_state][0] > priority:
                 update_priority(fringe, new_node, priority)
 
             else:
@@ -184,7 +184,7 @@ counter = itertools.count()     # unique sequence count
 def add_node(heap, node: Node, priority):
     count = next(counter)
     entry = [priority, count, node]
-    entry_finder[node.state] = entry
+    entry_finder[(node.state.row, node.state.column, node.state.direction)] = entry
     heappush(heap, entry)
 
 
@@ -192,12 +192,12 @@ def pop_node(heap):
     while heap:
         priority, count, node = heappop(heap)
         if node is not REMOVED:
-            del entry_finder[node.state]
+            del entry_finder[(node.state.row, node.state.column, node.state.direction)]
             return node
     return None
 
 
 def update_priority(heap, new_node, new_priority):
-    old_entry = entry_finder.pop(new_node.state)
+    old_entry = entry_finder.pop((new_node.state.row, new_node.state.column, new_node.state.direction))
     old_entry[-1] = REMOVED
     add_node(heap, new_node, new_priority)