The prison with Ignissa in cell 77.38 is located on water, so freeing her isn't that simple. In my case (since I'm playing as Necromancers, and the guard only allows Xeron to pass), the AI enemy, Pink, was able to free her, but then she just stayed there. After a while, I sailed over there and defeated Xeron, but when I tried to attack Ignissa, I suddenly saw the trade screen with a duplicate of my Necromancer prince instead of the battle screen. I tried different options: pure SoD, pure Complete Collection, WoG, I turned Fast Battle on and off, but the same thing happens everywhere.
The author warns the player about the problem in the events before the prison:
Ignissa: "You'll need either the Boots of Levitation or the Town Portal spell before you even think of rescuing me."
Author: Due to map design and a glitch in the game, in order for the Elemental Lord to learn all the spells, you will have to have her trade spells instead of your hero.
Here is my save file. If you don't mind, please check: does the bug repeat for you, and especially in the latest version of the HD mod (I haven't updated it in a long time)? If it can be overcome somehow, please tell me how? If not, then what should I do? The Fire Sphere will be needed later, but it's even more annoying that Ignissa has the Berserk spell, which I really need, because some of the attacking enemies are already too strong. There is a second Sphere on the map, but it's still far away and very well guarded.
(Василь Симоненко. Люди – прекрасні)