Modding

function ReturnArmy(combat)
  local n_stacks, id, count, died
  n_stacks = GetSavedCombatArmyCreaturesCount(combat, 0)
  for i = 0,(n_stacks-1) do
    id, count, died = GetSavedCombatArmyCreatureInfo(combat, 0, i)
    if GetHeroCreatures(GetSavedCombatArmyHero(combat, 0), id) ~= count then
      AddHeroCreatures(GetSavedCombatArmyHero(combat, 0), id, GetHeroCreatures(GetSavedCombatArmyHero(combat, 0), id) + died)
    end
  end
  n_stacks = GetSavedCombatArmyCreaturesCount(id, 1)
  for i = 0,(n_stacks-1) do
    id, count, died = GetSavedCombatArmyCreatureInfo(combat, 1, i)
    if GetHeroCreatures(GetSavedCombatArmyHero(combat, 1), id) ~= count then
      AddHeroCreatures(GetSavedCombatArmyHero(combat, 1), id, GetHeroCreatures(GetSavedCombatArmyHero(combat, 0), id) + died)
    end
  end
end

Trigger(COMBAT_RESULTS_TRIGGER, 'ReturnArmy')