The Ritual of Returning fires when you are "Injured" which is when you are hit by a spell or weapon (including missile fire) that does not kill you instantly.
If your commander is Routing and they rout without a province to rout to; he will die. It is often a good idea to not place units with someone with Ritual of Returning for that reason, as well as the fact that the commander can at any time pick up shop and fly home leaving his army standing around eating pudding snacks in enemy territory.
You can still get an Affliction from that one hit though. I personally have mixed feelings about this spell; it has a limited usefulness, but I'm sure for the "Rainbow" it's a terrific spell, if you can manage to survive the one hit
[ December 16, 2003, 00:21: Message edited by: Zen ]