Necromancer – “Assassination of the Ruler” [Campaign 3, Mission 4]

The mission is easily completed with the help of a single summon. The main thing is to learn the phoenix summon in the previous mission, and for battles (for example, against titans), deploy, for example, 20 dragons. Then the phoenix calmly flies forward and destroys 7-8 titans per turn, and the hero, if necessary, revives the dragons. The situation is even simpler if you have a celestial shield.
I didn't level up dark magic because there wasn't enough space (Summoning, defense, leadership, unfortunately, spellcasting, and luck were chosen!).