Mana regeneration seems to be my main problem with the game at this point. You can actually do a lot in the game with Magic - as it should be -, but amount of Mana all in all and mana regeneration seems to be insufficient to really use strategic spells to good and continous use. Teleporting around in your empire is fine, but once mana is expended, the specific hero is out of magicc for some turns.

With the manual being not very helpful - is there a way to regenerate more mana? How can a hero effectively expand the mana they can store?