"Escape to Salvation" - "Magnificent Retreat" [Campaign 4, Mission 4]

In version 3.0, you can stop Frida and not fight at all ;). But everything is calculated in the game, so you can guarantee defeat the demon with Frida. Don't forget that when she uses Light magic spells, "Divine Retribution" is cast on a random enemy unit. And that's very helpful. Moreover, if you use "Divine Retribution" with Frida, two of them will be triggered at once :)!