Veres:
After winning a battle where various living horses, unicorns, and riders were destroyed, the hero receives Death Knights. The bonus depends on the number of required creatures killed.
And I will continue to try to come up with a unique special ability: Cultist - at the beginning of each turn, the hero can use his special ability "Sacrifice," killing 50% of the selected creatures, in exchange gaining their "attack" and "defense" as his own characteristics.