For Demons – improve the catapult; now, during a castle siege, they can fire flaming projectiles, meaning they can target units (like a fire sprite) from 1 to 3 times.
For Necromancers – Soul Totem; when an enemy dies, their soul is taken and transformed into power, which is given to the Necromancer's warriors (all receive an amount of health equal to the killed unit; it acts like regeneration for vampires, but only when the entire stack is destroyed).
Added after 17 hours and 56 minutes
Also, Demons could be given a cauldron of imps (a soul cauldron) – after a battle, it collects a certain number of souls of fallen enemies, which, upon arrival in the city (or after the battle), turn into demons (their number and level depend on the number of souls in the cauldron)...
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