src/de/steamwar/lobby/listener/PlayerMoveListener.java

@@ -20,6 +20,7 @@
 package de.steamwar.lobby.listener;
 
 import de.steamwar.lobby.utils.Config;
+import org.bukkit.Bukkit;
 import org.bukkit.Location;
 import org.bukkit.event.EventHandler;
 import org.bukkit.event.Listener;
@@ -28,12 +29,17 @@ import org.bukkit.util.Vector;
 
 public class PlayerMoveListener implements Listener {
 
+    private static final Location spawnLocation = new Location(Bukkit.getWorlds().get(0), Config.SpawnX, Config.SpawnY, Config.SpawnZ, Config.Yaw, Config.Pitch);
+
     private static final Vector borderMinVector = new Vector(Config.BorderMinX, Config.BorderMinY, Config.BorderMinZ);
     private static final Vector borderMaxVector = new Vector(Config.BorderMaxX, Config.BorderMaxY, Config.BorderMaxZ);
 
     @EventHandler
     public void handleWorldBorder(PlayerMoveEvent event) {
         Location to = event.getTo();
+        if (to.getY() < 0) {
+            event.getPlayer().teleport(spawnLocation);
+        }
         if (!to.toVector().isInAABB(borderMinVector, borderMaxVector)) {
             event.getPlayer().teleport(event.getFrom());
         }