diff --git a/src/base_system.nvgt b/src/base_system.nvgt
index fdc9cfd..a401899 100644
--- a/src/base_system.nvgt
+++ b/src/base_system.nvgt
@@ -37,3 +37,115 @@ void keep_base_fires_fed() {
         break;
     }
 }
+
+// Resident defense functions
+int get_available_defense_weapons() {
+    int count = storage_spears;
+    // Slings only count if stones are available
+    if (storage_slings > 0 && storage_stones > 0) {
+        count += storage_slings;
+    }
+    return count;
+}
+
+bool can_residents_defend() {
+    if (residents_count <= 0) return false;
+    return get_available_defense_weapons() > 0;
+}
+
+bool choose_defense_weapon() {
+    // Returns true for spear, false for sling
+    int spearCount = storage_spears;
+    int slingCount = (storage_slings > 0 && storage_stones > 0) ? storage_slings : 0;
+    int total = spearCount + slingCount;
+
+    if (total == 0) return true;
+    if (slingCount == 0) return true;
+    if (spearCount == 0) return false;
+
+    int roll = random(1, total);
+    return roll <= spearCount;
+}
+
+int perform_resident_defense() {
+    if (!can_residents_defend()) return 0;
+
+    // Choose weapon type randomly weighted by availability
+    bool useSpear = choose_defense_weapon();
+
+    int damage = 0;
+    if (useSpear && storage_spears > 0) {
+        damage = RESIDENT_SPEAR_DAMAGE;
+        play_1d_with_volume_step("sounds/weapons/spear_swing.ogg", x, BASE_END + 1, false, 3.0);
+    } else if (storage_slings > 0 && storage_stones > 0) {
+        damage = random(RESIDENT_SLING_DAMAGE_MIN, RESIDENT_SLING_DAMAGE_MAX);
+        storage_stones--;
+        play_1d_with_volume_step("sounds/weapons/sling_hit.ogg", x, BASE_END + 1, false, 3.0);
+    }
+
+    return damage;
+}
+
+void process_daily_weapon_breakage() {
+    if (residents_count <= 0) return;
+
+    int totalWeapons = storage_spears + storage_slings;
+    if (totalWeapons == 0) return;
+
+    // Number of breakage checks = min(residents, weapons)
+    int checksToPerform = (residents_count < totalWeapons) ? residents_count : totalWeapons;
+
+    // Distribute checks among available weapons
+    int spearChecks = 0;
+    int slingChecks = 0;
+
+    for (int i = 0; i < checksToPerform; i++) {
+        int remainingSpears = storage_spears - spearChecks;
+        int remainingSlings = storage_slings - slingChecks;
+        int remaining = remainingSpears + remainingSlings;
+
+        if (remaining <= 0) break;
+
+        int roll = random(1, remaining);
+        if (roll <= remainingSpears && remainingSpears > 0) {
+            spearChecks++;
+        } else if (remainingSlings > 0) {
+            slingChecks++;
+        }
+    }
+
+    // Perform breakage checks
+    int spearsBroken = 0;
+    int slingsBroken = 0;
+
+    for (int i = 0; i < spearChecks; i++) {
+        if (random(1, 100) <= RESIDENT_WEAPON_BREAK_CHANCE) {
+            spearsBroken++;
+        }
+    }
+
+    for (int i = 0; i < slingChecks; i++) {
+        if (random(1, 100) <= RESIDENT_WEAPON_BREAK_CHANCE) {
+            slingsBroken++;
+        }
+    }
+
+    // Apply breakage
+    if (spearsBroken > 0) {
+        storage_spears -= spearsBroken;
+        if (storage_spears < 0) storage_spears = 0;
+        string msg = (spearsBroken == 1)
+            ? "A resident's spear broke from wear."
+            : spearsBroken + " spears broke from wear.";
+        notify(msg);
+    }
+
+    if (slingsBroken > 0) {
+        storage_slings -= slingsBroken;
+        if (storage_slings < 0) storage_slings = 0;
+        string msg = (slingsBroken == 1)
+            ? "A resident's sling broke from wear."
+            : slingsBroken + " slings broke from wear.";
+        notify(msg);
+    }
+}
diff --git a/src/constants.nvgt b/src/constants.nvgt
index 67c00f5..18bc0e8 100644
--- a/src/constants.nvgt
+++ b/src/constants.nvgt
@@ -97,3 +97,9 @@ const double QUEST_FAVOR_PER_POINT = 0.05;
 const int QUEST_STONE_SCORE = 6;
 const int QUEST_LOG_SCORE = 10;
 const int QUEST_SKIN_SCORE = 14;
+
+// Resident defense settings
+const int RESIDENT_WEAPON_BREAK_CHANCE = 10;
+const int RESIDENT_SPEAR_DAMAGE = 2;
+const int RESIDENT_SLING_DAMAGE_MIN = 3;
+const int RESIDENT_SLING_DAMAGE_MAX = 5;
diff --git a/src/time_system.nvgt b/src/time_system.nvgt
index 411de9a..a035a6f 100644
--- a/src/time_system.nvgt
+++ b/src/time_system.nvgt
@@ -153,12 +153,12 @@ void check_scheduled_invasion() {
 void attempt_daily_invasion() {
     if (current_day < 2) return;
     if (invasion_triggered_today || invasion_active) return;
-    if (invasion_roll_done_today) return;
-    invasion_roll_done_today = true;
+    if (current_hour < 6 || current_hour > 12) return;
 
     int roll = random(1, 100);
     if (roll > invasion_chance) return;
 
+    invasion_triggered_today = true;
     schedule_invasion();
     check_scheduled_invasion();
 }
@@ -305,7 +305,6 @@ void update_time() {
 
         check_ambience_transition();
 
-        // TODO: add resident defense using stored weapons once storage exists.
         if (is_daytime && residents_count > 0 && barricade_health < BARRICADE_MAX_HEALTH && current_hour % 4 == 0) {
             if (storage_meat > 0) {
                 int gained = add_barricade_health(residents_count);
@@ -317,12 +316,10 @@ void update_time() {
 
         if (current_hour == 6) {
             save_game_state();
-        }
-
-        if (current_hour == 6) {
-            attempt_daily_invasion();
+            process_daily_weapon_breakage();
             attempt_daily_quest();
         }
+        attempt_daily_invasion();
         keep_base_fires_fed();
         check_scheduled_invasion();
         attempt_blessing();
diff --git a/src/world_state.nvgt b/src/world_state.nvgt
index 0a7d874..492ba4d 100644
--- a/src/world_state.nvgt
+++ b/src/world_state.nvgt
@@ -618,6 +618,17 @@ void try_attack_barricade(Zombie@ zombie) {
 
     play_1d_with_volume_step("sounds/enemies/zombie_hits_player.ogg", x, zombie.position, false, ZOMBIE_SOUND_VOLUME_STEP);
 
+    // Resident defense counter-attack
+    if (can_residents_defend()) {
+        int counterDamage = perform_resident_defense();
+        if (counterDamage > 0) {
+            zombie.health -= counterDamage;
+            if (zombie.health <= 0 && x <= BASE_END) {
+                screen_reader_speak("Residents killed an attacking zombie.", true);
+            }
+        }
+    }
+
     if (barricade_health == 0) {
         notify("The barricade has fallen!");
     }
@@ -859,6 +870,17 @@ void try_attack_barricade_bandit(Bandit@ bandit) {
         p.play_stationary("sounds/weapons/axe_hit.ogg", false);
     }
 
+    // Resident defense counter-attack
+    if (can_residents_defend()) {
+        int counterDamage = perform_resident_defense();
+        if (counterDamage > 0) {
+            bandit.health -= counterDamage;
+            if (bandit.health <= 0 && x <= BASE_END) {
+                screen_reader_speak("Residents killed an attacking bandit.", true);
+            }
+        }
+    }
+
     if (barricade_health == 0) {
         notify("The barricade has fallen!");
     }