Light Novel Volume 4

Descend of the Peerless Devil King (天下無双の魔王降臨, Tenka musō no maō kōrin) is the 4th Volume of the series Kenja no Mago.

Short Summary
The war between the Earlshide Kingdom and the Bluesphere Empire finally begins. However, everyone was only dancing on the palm of the demon Schtrom....