diff --git a/src/audio.h b/src/audio.h
index 8950980..a574a9a 100644
--- a/src/audio.h
+++ b/src/audio.h
@@ -25,4 +25,4 @@ void audio_play_player_damage(void);
 // Play stairs/level change sound
 void audio_play_stairs(void);
 
-#endif // AUDIO_H
+#endif  // AUDIO_H
diff --git a/src/combat.c b/src/combat.c
index 2caa0e5..064e4c8 100644
--- a/src/combat.c
+++ b/src/combat.c
@@ -11,11 +11,17 @@ typedef struct {
 
 static CombatEvent last_event = {NULL, 0, 0};
 
-const char *combat_get_last_message(void) { return last_event.message; }
+const char *combat_get_last_message(void) {
+  return last_event.message;
+}
 
-int combat_get_last_damage(void) { return last_event.damage; }
+int combat_get_last_damage(void) {
+  return last_event.damage;
+}
 
-int combat_was_player_damage(void) { return last_event.is_player_damage; }
+int combat_was_player_damage(void) {
+  return last_event.is_player_damage;
+}
 
 void combat_player_attack(Player *p, Enemy *e) {
   if (e == NULL || !e->alive)
diff --git a/src/combat.h b/src/combat.h
index cc44794..e969754 100644
--- a/src/combat.h
+++ b/src/combat.h
@@ -21,4 +21,4 @@ void combat_player_attack(Player *p, Enemy *e);
 // Enemy attacks player
 void combat_enemy_attack(Enemy *e, Player *p);
 
-#endif // COMBAT_H
+#endif  // COMBAT_H
diff --git a/src/enemy.h b/src/enemy.h
index fdd260b..d7b2e6c 100644
--- a/src/enemy.h
+++ b/src/enemy.h
@@ -10,6 +10,6 @@ void enemy_spawn(Enemy enemies[], int *count, Map *map, Player *p, int floor);
 void enemy_update_all(Enemy enemies[], int count, Player *p, Map *map);
 
 // Check if position has an enemy
-int is_enemy_at(Enemy *enemies, int count, int x, int y);
+int is_enemy_at(const Enemy *enemies, int count, int x, int y);
 
-#endif // ENEMY_H
+#endif  // ENEMY_H
diff --git a/src/items.c b/src/items.c
index ebe41eb..b5d3e6b 100644
--- a/src/items.c
+++ b/src/items.c
@@ -40,15 +40,15 @@ void item_spawn(Item items[], int *count, Map *map, int floor) {
     if (type_roll < 50) {
       // 50% chance for potion
       item.type = ITEM_POTION;
-      item.power = 5 + rng_int(0, floor * 2); // healing: 5 + 0-2*floor
+      item.power = 5 + rng_int(0, floor * 2);  // healing: 5 + 0-2*floor
     } else if (type_roll < 80) {
       // 30% chance for weapon
       item.type = ITEM_WEAPON;
-      item.power = 1 + rng_int(0, floor); // attack bonus: 1 + 0-floor
+      item.power = 1 + rng_int(0, floor);  // attack bonus: 1 + 0-floor
     } else {
       // 20% chance for armor
       item.type = ITEM_ARMOR;
-      item.power = 1 + rng_int(0, floor / 2); // defense bonus
+      item.power = 1 + rng_int(0, floor / 2);  // defense bonus
     }
 
     items[i] = item;
diff --git a/src/items.h b/src/items.h
index c54e827..7798323 100644
--- a/src/items.h
+++ b/src/items.h
@@ -11,4 +11,4 @@ void item_spawn(Item items[], int *count, Map *map, int floor);
 // Use an item
 void item_use(Player *p, Item *i);
 
-#endif // ITEMS_H
+#endif  // ITEMS_H
diff --git a/src/main.c b/src/main.c
index e08d341..9430bfd 100644
--- a/src/main.c
+++ b/src/main.c
@@ -10,57 +10,42 @@
 #include "rng.h"
 #include "settings.h"
 #include <stddef.h>
-
-// Global game state
-static Player player;
-static Map map;
-static Dungeon dungeon;
-static Enemy enemies[MAX_ENEMIES];
-static int enemy_count;
-static Item items[MAX_ITEMS];
-static int item_count;
-static int game_over = 0;
-static int game_won = 0;
-static const char *last_message = NULL;
-static int message_timer = 0;
-
-// Turn counter for enemy movement (enemies move every other turn)
-static int turn_count = 0;
+#include <string.h>
 
 // Initialize a new floor
-static void init_floor(int floor_num) {
+static void init_floor(GameState *gs, int floor_num) {
   // Generate dungeon
-  dungeon_generate(&dungeon, &map, floor_num);
+  dungeon_generate(&gs->dungeon, &gs->map, floor_num);
 
   // Seed rng for this floor's content
   rng_seed(floor_num * 54321);
 
   // Find spawn position
   int start_x, start_y;
-  get_random_floor_tile(&map, &start_x, &start_y, 100);
+  get_random_floor_tile(&gs->map, &start_x, &start_y, 100);
 
   // Initialize player position if first floor
   if (floor_num == 1) {
-    player_init(&player, start_x, start_y);
+    player_init(&gs->player, start_x, start_y);
   } else {
     // Move player to new floor position
-    player.x = start_x;
-    player.y = start_y;
+    gs->player.x = start_x;
+    gs->player.y = start_y;
   }
-  player.floor = floor_num;
+  gs->player.floor = floor_num;
 
   // Spawn enemies
-  enemy_spawn(enemies, &enemy_count, &map, &player, floor_num);
+  enemy_spawn(gs->enemies, &gs->enemy_count, &gs->map, &gs->player, floor_num);
 
   // Spawn items
-  item_spawn(items, &item_count, &map, floor_num);
+  item_spawn(gs->items, &gs->item_count, &gs->map, floor_num);
 
   // Reset turn counter
-  turn_count = 0;
+  gs->turn_count = 0;
 }
 
-// Handle player input - returns: 0=continue, -1=quit
-static int handle_input(void) {
+// Handle player input - returns: 0=continue, 1=acted, -1=quit
+static int handle_input(GameState *gs) {
   int dx = 0, dy = 0;
 
   // Check for quit first (always works)
@@ -69,21 +54,20 @@ static int handle_input(void) {
   }
 
   // Check for restart (works during game over)
-  if (IsKeyPressed(KEY_R) && game_over) {
-    game_over = 0;
-    game_won = 0;
-    init_floor(1);
+  if (IsKeyPressed(KEY_R) && gs->game_over) {
+    memset(gs, 0, sizeof(GameState));
+    init_floor(gs, 1);
     return 0;
   }
 
   // Check for item usage (U key)
-  if (IsKeyPressed(KEY_U) && !game_over) {
-    if (player.inventory_count > 0) {
-      if (player_use_first_item(&player)) {
-        last_message = "Used item!";
-        message_timer = 60;
+  if (IsKeyPressed(KEY_U) && !gs->game_over) {
+    if (gs->player.inventory_count > 0) {
+      if (player_use_first_item(&gs->player)) {
+        gs->last_message = "Used item!";
+        gs->message_timer = 60;
         audio_play_item_pickup();
-        return 1; // consume a turn
+        return 1;  // consume a turn
       }
     }
   }
@@ -103,45 +87,56 @@ static int handle_input(void) {
     // Reset combat message
     combat_reset_event();
 
-    // Player action
+    // Check for item at target position before moving
+    int new_x = gs->player.x + dx;
+    int new_y = gs->player.y + dy;
+    int will_pickup = 0;
+    for (int i = 0; i < gs->item_count; i++) {
+      if (!gs->items[i].picked_up && gs->items[i].x == new_x && gs->items[i].y == new_y) {
+        will_pickup = 1;
+        break;
+      }
+    }
 
-    int action = player_move(&player, dx, dy, &map, enemies, enemy_count, items,
-                             item_count);
+    // Player action
+    int action = player_move(&gs->player, dx, dy, &gs->map, gs->enemies, gs->enemy_count, gs->items, gs->item_count);
 
     if (action) {
+      // Play pickup sound if item was picked up
+      if (will_pickup) {
+        audio_play_item_pickup();
+      }
       // Increment turn counter
-      turn_count++;
+      gs->turn_count++;
 
       // Check if stepped on stairs
-
-      if (map.tiles[player.y][player.x] == TILE_STAIRS) {
+      if (gs->map.tiles[gs->player.y][gs->player.x] == TILE_STAIRS) {
         // Go to next floor
-        if (player.floor < NUM_FLOORS) {
+        if (gs->player.floor < NUM_FLOORS) {
           audio_play_stairs();
-          init_floor(player.floor + 1);
-          last_message = "Descended to next floor!";
-          message_timer = 60;
+          init_floor(gs, gs->player.floor + 1);
+          gs->last_message = "Descended to next floor!";
+          gs->message_timer = 60;
         } else {
           // Won the game
-          game_won = 1;
-          game_over = 1;
+          gs->game_won = 1;
+          gs->game_over = 1;
         }
       }
 
       // Check if killed enemy
-
       if (combat_get_last_message() != NULL && !combat_was_player_damage()) {
         // Check if enemy died
-        for (int i = 0; i < enemy_count; i++) {
-          if (!enemies[i].alive) {
+        for (int i = 0; i < gs->enemy_count; i++) {
+          if (!gs->enemies[i].alive) {
             audio_play_enemy_death();
           }
         }
       }
 
       // Enemy turn - only every other turn for fairness
-      if (turn_count % 2 == 0) {
-        enemy_update_all(enemies, enemy_count, &player, &map);
+      if (gs->turn_count % 2 == 0) {
+        enemy_update_all(gs->enemies, gs->enemy_count, &gs->player, &gs->map);
       }
 
       // Check if player took damage
@@ -150,12 +145,12 @@ static int handle_input(void) {
       }
 
       // Set message
-      last_message = combat_get_last_message();
-      message_timer = 60;
+      gs->last_message = combat_get_last_message();
+      gs->message_timer = 60;
 
       // Check game over
-      if (player.hp <= 0) {
-        game_over = 1;
+      if (gs->player.hp <= 0) {
+        gs->game_over = 1;
       }
     }
   }
@@ -165,17 +160,20 @@ static int handle_input(void) {
 
 // Main game loop
 static void game_loop(void) {
+  GameState gs;
+  memset(&gs, 0, sizeof(GameState));
+
   // Initialize first floor
   rng_seed(12345);
-  init_floor(1);
+  init_floor(&gs, 1);
 
   // Disable esc to exit
   SetExitKey(0);
 
   while (!WindowShouldClose()) {
     // Handle input
-    if (!game_over) {
-      int quit = handle_input();
+    if (!gs.game_over) {
+      int quit = handle_input(&gs);
       if (quit == -1)
         break;
     } else {
@@ -183,41 +181,41 @@ static void game_loop(void) {
       if (IsKeyPressed(KEY_Q))
         break;
       if (IsKeyPressed(KEY_R)) {
-        game_over = 0;
-        game_won = 0;
-        init_floor(1);
+        memset(&gs, 0, sizeof(GameState));
+        gs.game_over = 0;
+        gs.game_won = 0;
+        init_floor(&gs, 1);
       }
     }
 
     // Update message timer
-    if (message_timer > 0)
-      message_timer--;
+    if (gs.message_timer > 0)
+      gs.message_timer--;
 
     // Render
     BeginDrawing();
     ClearBackground(BLACK);
 
     // Draw game elements
-    render_map(&map);
-    render_items(items, item_count);
-    render_enemies(enemies, enemy_count);
-    render_player(&player);
-    render_ui(&player);
+    render_map(&gs.map);
+    render_items(gs.items, gs.item_count);
+    render_enemies(gs.enemies, gs.enemy_count);
+    render_player(&gs.player);
+    render_ui(&gs.player);
 
     // Draw message if any
-    if (last_message != NULL && message_timer > 0) {
-      render_message(last_message);
+    if (gs.last_message != NULL && gs.message_timer > 0) {
+      render_message(gs.last_message);
     }
 
     // Draw game over screen
-    if (game_over) {
+    if (gs.game_over) {
       render_game_over();
-      if (game_won) {
+      if (gs.game_won) {
         // Draw win message
         const char *win_msg = "YOU WIN! ESCAPED THE DUNGEON!";
         int msg_w = MeasureText(win_msg, 30);
-        DrawText(win_msg, (SCREEN_WIDTH - msg_w) / 2, SCREEN_HEIGHT / 2 - 80,
-                 30, GOLD);
+        DrawText(win_msg, (SCREEN_WIDTH - msg_w) / 2, SCREEN_HEIGHT / 2 - 80, 30, GOLD);
       }
     }
 
diff --git a/src/player.h b/src/player.h
index c7cd3fa..0ccab25 100644
--- a/src/player.h
+++ b/src/player.h
@@ -7,8 +7,7 @@
 void player_init(Player *p, int x, int y);
 
 // Move player, return 1 if moved/attacked, 0 if blocked
-int player_move(Player *p, int dx, int dy, Map *map, Enemy *enemies,
-                int enemy_count, Item *items, int item_count);
+int player_move(Player *p, int dx, int dy, Map *map, Enemy *enemies, int enemy_count, Item *items, int item_count);
 
 // Player attacks enemy (deal damage)
 void player_attack(Player *p, Enemy *e);
@@ -25,4 +24,4 @@ int player_use_first_item(Player *p);
 // Get item at inventory index, returns NULL if invalid
 Item *player_get_inventory_item(Player *p, int index);
 
-#endif // PLAYER_H
+#endif  // PLAYER_H
diff --git a/src/render.h b/src/render.h
index 32e26e7..6ec6469 100644
--- a/src/render.h
+++ b/src/render.h
@@ -4,19 +4,19 @@
 #include "common.h"
 
 // Render the map tiles
-void render_map(Map *map);
+void render_map(const Map *map);
 
 // Render the player
-void render_player(Player *p);
+void render_player(const Player *p);
 
 // Render all enemies
-void render_enemies(Enemy *enemies, int count);
+void render_enemies(const Enemy *enemies, int count);
 
 // Render all items
-void render_items(Item *items, int count);
+void render_items(const Item *items, int count);
 
 // Render UI overlay
-void render_ui(Player *p);
+void render_ui(const Player *p);
 
 // Render game over screen
 void render_game_over(void);
@@ -24,4 +24,4 @@ void render_game_over(void);
 // Render a message popup
 void render_message(const char *message);
 
-#endif // RENDER_H
+#endif  // RENDER_H
diff --git a/src/rng.c b/src/rng.c
index 2efcce7..62d6fcf 100644
--- a/src/rng.c
+++ b/src/rng.c
@@ -6,7 +6,7 @@ static unsigned int g_seed = 1;
 // LCG parameters (from numerical recipes)
 #define LCG_A 1664525
 #define LCG_C 1013904223
-#define LCG_MOD 4294967294 // 2^32 - 2 (avoid 0)
+#define LCG_MOD 4294967294  // 2^32 - 2 (avoid 0)
 
 void rng_seed(unsigned int seed) {
   // Ensure seed is never 0
diff --git a/src/rng.h b/src/rng.h
index 94bad67..a89c798 100644
--- a/src/rng.h
+++ b/src/rng.h
@@ -7,4 +7,4 @@ void rng_seed(unsigned int seed);
 // Get a random integer in range [min, max]
 int rng_int(int min, int max);
 
-#endif // RNG_H
+#endif  // RNG_H
diff --git a/src/settings.h b/src/settings.h
index d5978fb..47f3c12 100644
--- a/src/settings.h
+++ b/src/settings.h
@@ -25,4 +25,4 @@
 #define NUM_FLOORS 5
 #define MAX_INVENTORY 10
 
-#endif // SETTINGS_H
+#endif  // SETTINGS_H
diff --git a/src/utils.h b/src/utils.h
index e638c0d..211cf44 100644
--- a/src/utils.h
+++ b/src/utils.h
@@ -7,4 +7,4 @@ int clamp(int value, int min, int max);
 // Check if coordinates are within map bounds
 int in_bounds(int x, int y, int width, int height);
 
-#endif // UTILS_H
+#endif  // UTILS_H