What can I say, after a Dragon and an Ettin it's one of the more regular beasts, plus, magic should never surprise a wizard of Rantic's Stature, pah!
Did Torma tell Danton about his bat transformation ability? If so, Danton will know not to strike at any bats.
He doesnt ! However he'll by flying rather high, you d need a pretty good intuition to find and hit a suddenly appearing, almost silent bat in pitch black.
That's why you zombify it, put it in my robe, and walk through the door, and then let it exit the robe again