In Heian-Jidai's 12th century period, many internal tensions occurred with the increasing power of the clans alongside the imperial court, where mysterious supernatural phenomena occurred.In Heian-Jidai's 12th century period, many internal tensions occurred with the increasing power of the clans alongside the imperial court, where mysterious supernatural phenomena occurred.In Heian-Jidai's 12th century period, many internal tensions occurred with the increasing power of the clans alongside the imperial court, where mysterious supernatural phenomena occurred.