LobbyDamageListener.java

    @Listener
    public void onDamage(DamageEntityEvent event) {
        if(this.lobby.is(event.getTargetEntity().getWorld())) {
            event.setCancelled(true);
            if (event.getCause().any(DamageSource.class) && event.getCause().first(DamageSource.class).get() == DamageSources.VOID && event.getTargetEntity() instanceof Player) {
                event.getTargetEntity().setLocation(this.lobby.getSpawn());
            }
        }
    }