diff --git a/worlds/pokemon_rb/regions.py b/worlds/pokemon_rb/regions.py
index 1816d010..f8449765 100644
--- a/worlds/pokemon_rb/regions.py
+++ b/worlds/pokemon_rb/regions.py
@@ -1594,7 +1594,7 @@ def create_regions(self):
     connect(multiworld, player, "Menu", "Pallet Town", one_way=True)
     connect(multiworld, player, "Menu", "Pokedex", one_way=True)
     connect(multiworld, player, "Menu", "Evolution", one_way=True)
-    connect(multiworld, player, "Menu", "Fossil", lambda state: logic.fossil_checks(state, 
+    connect(multiworld, player, "Menu", "Fossil", lambda state: logic.fossil_checks(state,
         state.multiworld.second_fossil_check_condition[player].value, player), one_way=True)
     connect(multiworld, player, "Pallet Town", "Route 1")
     connect(multiworld, player, "Route 1", "Viridian City")
@@ -2269,23 +2269,28 @@ def create_regions(self):
 
         event_locations = self.multiworld.get_filled_locations(player)
 
-        def adds_reachable_entrances(entrances_copy, item):
+        def adds_reachable_entrances(entrances_copy, item, dead_end_cache):
+            ret = dead_end_cache.get(item.name)
+            if (ret != None):
+                return ret
+
             state_copy = state.copy()
             state_copy.collect(item, True)
             state.sweep_for_events(locations=event_locations)
             ret = len([entrance for entrance in entrances_copy if entrance in reachable_entrances or
                       entrance.parent_region.can_reach(state_copy)]) > len(reachable_entrances)
+            dead_end_cache[item.name] = ret
             return ret
 
-        def dead_end(entrances_copy, e):
+        def dead_end(entrances_copy, e, dead_end_cache):
             region = e.parent_region
             check_warps = set()
             checked_regions = {region}
             check_warps.update(region.exits)
             check_warps.remove(e)
             for location in region.locations:
-                if location.item and location.item.name in relevant_events and adds_reachable_entrances(entrances_copy,
-                                                                                                        location.item):
+                if location.item and location.item.name in relevant_events and \
+                                 adds_reachable_entrances(entrances_copy, location.item, dead_end_cache):
                     return False
             while check_warps:
                 warp = check_warps.pop()
@@ -2302,7 +2307,7 @@ def create_regions(self):
                                 check_warps.update(warp.connected_region.exits)
                                 for location in warp.connected_region.locations:
                                     if (location.item and location.item.name in relevant_events and
-                                            adds_reachable_entrances(entrances_copy, location.item)):
+                                            adds_reachable_entrances(entrances_copy, location.item, dead_end_cache)):
                                         return False
             return True
 
@@ -2332,6 +2337,8 @@ def create_regions(self):
             if multiworld.door_shuffle[player] == "full" or len(entrances) != len(reachable_entrances):
                 entrances.sort(key=lambda e: e.name not in entrance_only)
 
+                dead_end_cache = {}
+
                 # entrances list is empty while it's being sorted, must pass a copy to iterate through
                 entrances_copy = entrances.copy()
                 if multiworld.door_shuffle[player] == "decoupled":
@@ -2342,10 +2349,10 @@ def create_regions(self):
                 elif len(reachable_entrances) > (1 if multiworld.door_shuffle[player] == "insanity" else 8) and len(
                         entrances) <= (starting_entrances - 3):
                     entrances.sort(key=lambda e: 0 if e in reachable_entrances else 2 if
-                                   dead_end(entrances_copy, e) else 1)
+                                   dead_end(entrances_copy, e, dead_end_cache) else 1)
                 else:
                     entrances.sort(key=lambda e: 0 if e in reachable_entrances else 1 if
-                                   dead_end(entrances_copy, e) else 2)
+                                   dead_end(entrances_copy, e, dead_end_cache) else 2)
                 if multiworld.door_shuffle[player] == "full":
                     outdoor = outdoor_map(entrances[0].parent_region.name)
                     if len(entrances) < 48 and not outdoor: