Topic: Prayer (to Dark Gods) (9th ed)

[Exalted One]

Hiya,
Still learning the 9th ed. even though the 10th is up.
Anyway, I cannot find where the priest's prayers' activation is explained in any of the rulebooks. All the prayers start with the word "if the prayer is heard" - where does is say how the prayers are activated? How do I find out whether they get heard or not? The key here being where can I see the rule written?

[Wyddr]

It's in the core rules, somewhere in the same neighborhood as where they explain psychic tests and stuff. Probably under "Characters." I don't have the BRB in front of me, but it's definitely in there. Prayers are heard on a 3+, if memory serves.