diff --git a/src/Main.cc b/src/Main.cc
index b26c3066..c4e7a8b8 100644
--- a/src/Main.cc
+++ b/src/Main.cc
@@ -3191,8 +3191,8 @@ Action a_optimize_materialized_map(
           and parameters). Event count always takes precedence; that is, a map\n\
           with fewer events is always considered better than any map with more\n\
           events, regardless of the enemy counts.\n\
-      --restrict-room=ROOM-ID: Ignore all enemies outside of this room (may be\n\
-          given multiple times).\n\
+      --restrict-room=FLOOR:ROOM-ID: Ignore all enemies outside of this room\n\
+          (may be given multiple times).\n\
       --threads=NUM-THREADS: Limits parallelism; by default, uses one thread\n\
           per CPU core.\n\
       --debug: Enables debug logging.\n\
@@ -3214,12 +3214,20 @@ Action a_optimize_materialized_map(
           minimize_types.emplace(std::stoul(arg, nullptr, 0), std::make_pair(0xFF, 0));
         } else if (tokens.size() == 3) {
           minimize_types.emplace(std::stoul(tokens[0], nullptr, 0), std::make_pair(std::stoul(tokens[1], nullptr, 0), std::stoul(tokens[2], nullptr, 0)));
+        } else {
+          throw std::runtime_error("invalid vlaue for --minimize");
         }
       }
 
-      std::unordered_set<uint16_t> room_ids;
+      std::unordered_set<uint32_t> floor_room_ids; // (floor << 16) | room_id
       for (const auto& arg : args.get_multi<std::string>("restrict-room")) {
-        room_ids.emplace(std::stoul(arg, nullptr, 0));
+        auto tokens = phosg::split(arg, ':');
+        if (tokens.size() != 2) {
+          throw std::runtime_error("invalid vlaue for --restrict-room");
+        }
+        uint8_t floor = std::stoul(tokens[0], nullptr, 0);
+        uint16_t room_id = std::stoul(tokens[1], nullptr, 0);
+        floor_room_ids.emplace((floor << 16) | room_id);
       }
 
       size_t num_threads = args.get<size_t>("threads", 0);
@@ -3230,8 +3238,11 @@ Action a_optimize_materialized_map(
         auto materialized = map_file->materialize_random_sections(seed);
 
         auto is_minimize_target = [&](const MapFile::EnemySetEntry& ene) -> bool {
-          if (!room_ids.empty() && !room_ids.count(ene.room)) {
-            return false;
+          if (!floor_room_ids.empty()) {
+            uint32_t floor_room_id_key = (ene.floor << 8) | ene.room;
+            if (!floor_room_ids.count(floor_room_id_key)) {
+              return false;
+            }
           }
           if (minimize_types.empty()) {
             return true;