Removed backup locations for Dungeon Only and Major Only algorithms. If item cannot be placed in the appropriate location, the seed will fail to generate instead.

Fill.py

@@ -279,6 +279,10 @@ def recovery_placement(item_to_place, locations, world, state, base_state, itemp
                 if spot_to_fill:
                     return spot_to_fill
             return None
+    # explicitly fail these cases
+    elif world.algorithm in ['dungeon_only', 'major_only']:
+        raise FillError(f'Rare placement for {world.algorithm} detected. {item_to_place} unable to be placed.'
+                        f' Try a different seed')
     else:
         other_locations = [x for x in locations if x not in attempted]
         for location in other_locations:
@@ -419,7 +423,7 @@ def distribute_items_restrictive(world, gftower_trash=False, fill_locations=None
         else:
             max_trash = gt_count
         scaled_trash = math.floor(max_trash * scale_factor)
-        if world.goal[player] in ['triforcehunt', 'trinity', 'ganonhunt']:
+        if world.goal[player] in ['triforcehunt', 'trinity', 'ganonhunt'] or world.algorithm == 'dungeon_only':
             gftower_trash_count = random.randint(scaled_trash, max_trash)
         else:
             gftower_trash_count = random.randint(0, scaled_trash)

RELEASENOTES.md

@@ -110,6 +110,7 @@ These are now independent of retro mode and have three options: None, Random, an
 # Bug Fixes and Notes
 
 * 1.2.0.17u
+  * Removed backup locations for Dungeon Only and Major Only algorithms. If item cannot be placed in the appropriate location, the seed will fail to generate instead 
   * Fix for Non-ER Inverted Experimental (Aga and GT weren't logically swapped)
   * Fix for customizer setting crystals to 0 for either GT/Ganon
 * 1.2.0.16u

source/item/FillUtil.py

@@ -151,9 +151,6 @@ def create_item_pool_config(world):
             config.item_pool[player] = determine_major_items(world, player)
             config.location_groups[0].locations = set(groups.locations)
             config.reserved_locations[player].update(groups.locations)
-            backup = (mode_grouping['Heart Pieces'] + mode_grouping['Dungeon Trash'] + mode_grouping['Shops']
-                      + mode_grouping['Overworld Trash'] + mode_grouping['GT Trash'] + mode_grouping['RetroShops'])
-            config.location_groups[1].locations = set(backup)
     elif world.algorithm == 'dungeon_only':
         config.location_groups = [
             LocationGroup('Dungeons'),
@@ -171,9 +168,6 @@ def create_item_pool_config(world):
         for player in range(1, world.players + 1):
             config.item_pool[player] = determine_major_items(world, player)
             config.location_groups[0].locations = set(dungeon_set)
-            backup = (mode_grouping['Heart Pieces'] + mode_grouping['Overworld Major']
-                      + mode_grouping['Overworld Trash'] + mode_grouping['Shops'] + mode_grouping['RetroShops'])
-            config.location_groups[1].locations = set(backup)
 
 
 def district_item_pool_config(world):
@@ -419,11 +413,7 @@ def filter_locations(item_to_place, locations, world, vanilla_skip=False, potion
         if item_to_place.name in config.item_pool[item_to_place.player]:
             restricted = config.location_groups[0].locations
             filtered = [l for l in locations if l.name in restricted]
-            if len(filtered) == 0:
+            return filtered
-                restricted = config.location_groups[1].locations
-                filtered = [l for l in locations if l.name in restricted]
-                # bias toward certain location in overflow? (thinking about this for major_bias)
-            return filtered if len(filtered) > 0 else locations
     if world.algorithm == 'district':
         config = world.item_pool_config
         if ((isinstance(item_to_place,str) and item_to_place == 'Placeholder')