Suggestion for a new faction.

The whole point here is to have a unit that is an elemental and the strongest, and also to be able to summon it. Additionally, there should be an option to cast a spell to summon sea elementals, but only for this castle, and a hero should be created – let's call him Sarrus for now – whose specialization will be +1 to the defense and attack of these monsters, plus for every 3 levels, he gains 1 unit of magic power for the spell to summon them, and the hero starts with this spell.