diff --git a/include/globals.h b/include/globals.h
index 8bb1ea4..e655916 100644
--- a/include/globals.h
+++ b/include/globals.h
@@ -76,7 +76,7 @@ typedef struct {
   char name[16];
   int client_fd;
   short x;
-  short y;
+  uint8_t y;
   short z;
   short visited_x[VISITED_HISTORY];
   short visited_z[VISITED_HISTORY];
@@ -94,6 +94,7 @@ typedef struct {
   uint8_t inventory_count[41];
   uint8_t craft_count[9];
   // 0x01 - attack cooldown
+  // 0x02 - has not spawned yet
   uint8_t flags;
 } PlayerData;
 
diff --git a/src/main.c b/src/main.c
index dbfe484..979672b 100644
--- a/src/main.c
+++ b/src/main.c
@@ -167,7 +167,7 @@ void handlePacket (int client_fd, int length, int packet_id) {
 
         // Handle fall damage
         if (on_ground) {
-          int8_t damage = player->grounded_y - player->y - 3;
+          int16_t damage = player->grounded_y - player->y - 3;
           if (damage > 0 && getBlockAt(player->x, player->y, player->z) != B_water) {
             hurtEntity(client_fd, -1, D_fall, damage);
           }
@@ -224,6 +224,15 @@ void handlePacket (int client_fd, int length, int packet_id) {
         short dx = _x - (player->x < 0 ? player->x - 16 : player->x) / 16;
         short dz = _z - (player->z < 0 ? player->z - 16 : player->z) / 16;
 
+        // Prevent players from leaving the world
+        if (cy < 0) {
+          cy = 0;
+          sc_synchronizePlayerPosition(client_fd, cx, 0, cz, player->yaw * 180 / 127, player->pitch * 90 / 127);
+        } else if (cy > 255) {
+          cy = 255;
+          sc_synchronizePlayerPosition(client_fd, cx, 255, cz, player->yaw * 180 / 127, player->pitch * 90 / 127);
+        }
+
         // Update position in player data
         player->x = cx;
         player->y = cy;
diff --git a/src/procedures.c b/src/procedures.c
index 1b900f3..1a78cd9 100644
--- a/src/procedures.c
+++ b/src/procedures.c
@@ -47,7 +47,8 @@ void resetPlayerData (PlayerData *player) {
   player->hunger = 20;
   player->x = 8;
   player->z = 8;
-  player->y = -32767;
+  player->y = 0;
+  player->flags &= 0x02;
   player->grounded_y = 0;
   for (int i = 0; i < 41; i ++) {
     player->inventory_items[i] = 0;
@@ -203,7 +204,7 @@ void spawnPlayer (PlayerData *player) {
   float spawn_x = 8.5f, spawn_y = 80.0f, spawn_z = 8.5f;
   float spawn_yaw = 0.0f, spawn_pitch = 0.0f;
 
-  if (player->y == -32767) { // Is this a new player?
+  if ((player->flags & 0x02) == 0) { // Is this a new player?
     // Determine spawning Y coordinate based on terrain height
     spawn_y = getHeightAt(8, 8) + 1;
   } else { // Not a new player