This just happened to me in a battle with Morian, in the wildlands. I thought at first he hadn't spawned for the fight, as he wasn't visible off map, but clicked auto resolve and my mages found him. I never saw him myself, but recieved his goodies after a couple of rounds of spellslinging. 9 units in each army.
I didn't get a screenshot, but I may have a save before that battle, so could probably generate one, assuming it happened again.