Do no destroy all Virtual machines at the same time

Hi!

When I, for example, want to change something my terraform kills all Virtual Machines at the same time in my GCP Cloud. I want to kill the first machine after restore it and then kill the second machine and so on. Because I don’t want any downtime when it has a failover mode.
Do you have any ideas?

create_before_destroy (https://www.terraform.io/docs/configuration/resources.html#lifecycle-lifecycle-customizations)

An interesting article on deployment options:

Maybe this could help.