@SubscribeEvent
    public void onJoin(EntityJoinWorldEvent e){
        if (e.getEntity() instanceof EntityPlayer){
            EntityPlayer player = (EntityPlayer) e.getEntity();
            player.openGui(MiddleAgeCraft.instance, 0, player.world, (int) player.posX, (int) player.posY, (int) player.posZ);
        }
    }