Demon generals are a modern horror for non-professional players in this genre.
Therefore, the general strategy is as follows, for all generals:
1. Charge Celestian energy to 100%.
2. Read a book with tips in the library, especially about using sexual tricks to save health.
3. Before the battle, put on the most protective suit, for example, an elven one.
4. Before the battle, save the game to return to it after unsuccessful attempts. And also a stock of health potions and magic.
5. Well, and the general strategy: at the first attempt, try to use regular or strong spells, without using Celestian energy. To understand when the demon starts using cheat codes. Usually such things are tied to the demon's health bar.
6. At the next attempt, up to these values, you can use Celestian magic to freeze time and weaken the demon as much as possible.
7. If there is little health left, you need to try to use the magic of attraction. To do this, read the tips in the library and look for artifacts.
I passed with the help of Celestian energy and random experiments with potions, other players pass by combining different tactics.