Power is one possibility. More often, though, they cry out to their Primals for help. Or so I've gathered in my research.

[And a little bit of personal experience.]

To eliminate a threat, put an end to a battle, conclude wars. To defend their lost children. [Krile tilts her head a bit.] Is that not what your people would want from your gods?

[It is what Eorzeans want from the Twelve - to know that they are listening. That prayers can be answered.]