Oh my! They say that even the most experienced can make mistakes! It only dawned on me after iceTiTaN said, "Next, cast Berserk," how badly I messed up! :( The reason is that I learned from many battles with Necromancers that *they are almost immune to all mind control spells, even with the Vulnerability Aura*. I even opened the FizMiG specifically, but the information there is incomplete: *Blindness*, for example, never works on undead. So, I thought that Berserk was also useless against undead. But, of course, this battle could be won brilliantly with it: why waste Katusha's expert fire magic?
Also, I was in a hurry to finish this map after a 2-month break.
Now I can beat Haart without any losses! I'll try, at least.

"Dragons 1500... just stood there and skipped their turns"

And this is a feature of Berserk: if a stack controlled by the AI, under the effect of Berserk, cannot reach the nearest unit, it will indeed just skip its turns until the spell's effect wears off or is removed (see also in FizMiG).