Combat Arts, Spells, and Techniques
The Astros had many members, especially the people from the witch clan. He even brought children and old witches after accepting Amanda's allegiance. Not everyone in the witch clan was an expert so he naturally didn't know what to do with them. So he let them do what they were doing when they were still in the witch clan.
Simple farm and selling to make a living. Just the lives of ordinary people. They had different professions and most of the engineers that were working to build the wall were witches.
Also, Souta would copy Athen's Champion. He planned to create a portal here and establish a connection on the Guardian Fortress. Doranjan, Yuko, and the others were still staying in that place.
To create a portal, he had to use most of the savings that he kept. It would take a large number of resources as he also needs to create a portal on the Guardian Fortress. The resources needed depends on the distance between the two sides.