Easygoing Territory Defense by the Optimistic Lord: Production Magic Turns a Nameless Village into the Strongest Fortified City (Light Novel) Vol. 3

Van's carefree days of construction are numbered now that the neighboring kingdom has come to conquer. Once considered useless, his production magic arms his country's troops against the invasion! Meanwhile, one of Van's companions is horrified to discover that the enemy has set their sights on her hometown. Does his fellow magical misfit stand a chance against wyverns and explosives with the puppetry skills she so detests?