“Ashes’ Will” – “A Sad Journey” [Campaign 2, Mission 2]

No chaos is scary when everything is in one stack under the Celestial Shield.

I haven't really had a chance to use the Shield, so I'm not sure what you mean. Are you saying that if you line up units and cast Celestial Shield on the one in front, it will affect them all? Or are you suggesting keeping just one stack on the battlefield and casting the Shield on it?

And in general, nothing is scary for a well-developed Necropolis in this Campaign.

I'm not saying it's scary. Of course, you can still complete everything without it, but I just can't stand it when I get hit with Fireballs and Meteor Showers, and often the damage isn't even that high, like 800 units, but rather 180-300. However, the AI loves to attack in an area, especially where ranged units are, and in doing so, it hits a lot of units, no matter how much you move them around on the battlefield, because the Fireball has an area of effect that covers several squares. And if there are large units in the army, it makes the battle even more difficult, because in order not to have them destroyed, you often have to take them out of the battle and put them in reserve, because it is often impossible to restore them all by the end of the battle. Either the computer runs away, or the initiative doesn't reach the hero in time, or it triggers too early. And if you wait, the hero is pushed back quite a bit on the turn order, and in the end, it's a hassle again. So, I feel more comfortable with magic immunity than taking Logistics instead.
PS Actually, with the introduction of upgraded Liches in the third game, it has become easier, even though they don't fire their deadly cloud. Instead, they have Raise Dead in their spellbook. Now, even if the initiative doesn't reach the hero in time, you can use Liches as a backup, although this doesn't always work, because the computer often slows them down, the sneaky bastard