The org.wildfly.cloud:wildfly-cloud-galleon-pack Galleon feature-pack provisions a set of additional features allowing you to configure a WildFly server to work on the cloud.
Its usage is not strictly required when provisioning a WildFly server for the cloud, but as the detailed documentation describes, it brings to the server some configuration aspects that are generally expected in a cloud context (e.g.: Openshift or Kubernetes).
The org.wildfly.cloud:wildfly-cloud-preview-galleon-pack to be used with the org.wildfly:wildfly-preview-feature-pack (that allows to provision Jakarta EE 9+ server) provisions the same set of additional features.
Detailed documentation of the WildFly cloud Galleon feature-pack.