I gave you the tactic, iregev
The lineup I used is enough to beat him on impossible without losses, provided you ress (or use time back when their numbers dwindle too much) your scapegoat priests as soon as they die, so that Karador doesn't ress them as undead, in which case they will count as lost.
Also, in my eyes, priests are better than archers for that battle, because they do extra damage to undead, which dramatically improves their damage, which is very important on higher difficulties.