Masive update:

GameServer.objects(ip=ip).update(set__status=Server_status.STATUS_RUNNING)

You can use the double underscore:

Tournament.objects.filter(type__num_players=2)

Or raw queries:

Tournament.objects.filter(__raw__={'type.num_players': 2})
TournamentConfig.objects.filter(__raw__={'$where': 'this.type.num_players * this.type.num_teams == 4'})

Hacer queries con embedded objects:

gardens_with_flower0  = Garden.objects(flowers=flower0)
gardens_with_flower0_or_flower1  = Garden.objects(flowers__in=[flower0, flower1])
gardens_with_flower0_and_flower1  = Garden.objects(flowers__all=[flower0, flower1])

Añadiend - sería ordenar descendentemente:

people = Person.objects.order_by('last_name', '-age')