Lots of changes, forgot to add the heal scroll sound. Sounds for when enemies come in and go out of range. Menu filtering added.

src/time_system.nvgt

@@ -29,6 +29,12 @@ int invasion_chance = 25;
 bool invasion_triggered_today = false;
 bool invasion_roll_done_today = false;
 int invasion_scheduled_hour = -1;
+string invasion_enemy_type = "bandit";
+
+// Invasion mapping: "terrain=enemy" (defaults to bandits when no match)
+// Terrain keys: "mountain" for mountain ranges, or regular types like "grass", "snow", "forest", "deep_forest", "stone".
+string default_invasion_enemy_type = "bandit";
+string[] invasion_terrain_enemy_map = {"mountain=goblin"};
 
 void init_time() {
     current_hour = 8;
@@ -46,10 +52,37 @@ void init_time() {
     invasion_triggered_today = false;
     invasion_roll_done_today = false;
     invasion_scheduled_hour = -1;
+    invasion_enemy_type = "bandit";
     update_ambience(true); // Force start
 }
 
-void expand_area() {
+string get_invasion_enemy_type_for_terrain(const string&in terrain_type) {
+    for (uint i = 0; i < invasion_terrain_enemy_map.length(); i++) {
+        string entry = invasion_terrain_enemy_map[i];
+        int eq_pos = entry.find("=");
+        if (eq_pos <= 0) {
+            continue;
+        }
+
+        string key = entry.substr(0, eq_pos);
+        string value = entry.substr(eq_pos + 1);
+        if (key == terrain_type && value != "") {
+            return value;
+        }
+    }
+    return default_invasion_enemy_type;
+}
+
+string get_invasion_enemy_label(const string&in enemy_type) {
+    if (enemy_type != "") return enemy_type;
+    return default_invasion_enemy_type;
+}
+
+string get_invasion_enemy_plural(const string&in enemy_type) {
+    return get_invasion_enemy_label(enemy_type) + "s";
+}
+
+string expand_area() {
     // Play invasion sound
     p.play_stationary("sounds/enemies/invasion.ogg", false);
 
@@ -57,12 +90,13 @@ void expand_area() {
     int type_roll = random(0, 3);
     if (type_roll == 0) {
         expand_mountain();
-    } else {
-        expand_regular_area();
+        return "mountain";
     }
+
+    return expand_regular_area();
 }
 
-void expand_regular_area() {
+string expand_regular_area() {
     // Calculate new area
     int new_start = MAP_SIZE;
     int new_end = MAP_SIZE + EXPANSION_SIZE - 1;
@@ -120,6 +154,7 @@ void expand_regular_area() {
 
     area_expanded_today = true;
     notify("The area has expanded! New territory discovered to the east.");
+    return terrain_type;
 }
 
 void expand_mountain() {
@@ -147,10 +182,13 @@ void expand_mountain() {
 }
 
 void start_invasion() {
-    expand_area();
+    string expansion_terrain = expand_area();
     invasion_active = true;
     invasion_start_hour = current_hour;
-    notify("Bandits are invading from the new area!");
+    invasion_enemy_type = get_invasion_enemy_type_for_terrain(expansion_terrain);
+    string source = (expansion_terrain == "mountain") ? "the mountains" : "the new area";
+    string enemy_plural = get_invasion_enemy_plural(invasion_enemy_type);
+    notify(enemy_plural + " are invading from " + source + "!");
 }
 
 void update_invasion_chance_for_new_day() {
@@ -268,7 +306,7 @@ void end_invasion() {
     invasion_active = false;
     invasion_start_hour = -1;
     transition_bandits_to_wandering();
-    notify("The bandit invasion has ended.");
+    notify("The " + get_invasion_enemy_label(invasion_enemy_type) + " invasion has ended.");
     attempt_resident_recruitment();
 }
 
@@ -302,10 +340,10 @@ void manage_bandits_during_invasion() {
         return;
     }
 
-    // During daytime: if invasion is active, maintain bandit count
+    // During daytime: if invasion is active, maintain invader count
     if (invasion_active && expanded_area_start != -1) {
         while (bandits.length() < BANDIT_MAX_COUNT) {
-            spawn_bandit(expanded_area_start, expanded_area_end);
+            spawn_bandit(expanded_area_start, expanded_area_end, invasion_enemy_type);
         }
     }
     // If invasion not active, wandering bandits persist during daytime
@@ -448,7 +486,7 @@ void update_time() {
     // Proactive resident defense with slings
     attempt_resident_sling_defense();
 
-    // Manage bandits during active invasion
+    // Manage invasion enemies during active invasion
     manage_bandits_during_invasion();
 }