Power Master 1: A Strange Journey
In Power Master 1: A Strange Journey, Sleep Shields are rare shields that can only be bought at the Blacksmith in the Town of Yora. According to its description, it is created by fusing a Book of Sleep with a shield. When equipped, it increases the wielder's Defense by 20 and the wielder will be immune to the Asleep status. Additionally, the wielder will become strong to Dark-, Physical-, Light-, Stone-, and Weapon-based attacks.