No-Life King

The No-Life King (不死の王, Nō-Raifu Kingu; lit. Undying King) is a mysterious and powerful figure who once ruled Grimgar over a century ago. After his supposed defeat, his curse of the Undead still lingers in Grimgar.

He is an entity with no body of its own, but is able to possess living beings to act as his vessel. This process revives fresh corpses, keeping their consciousness as well as those of previous vessels, and the No-Life King himself. It also gives them access to knowledge and skills, such as magic, known by previous vessels.

The No-Life King claims his wish was to live together with humans, but he was hated and feared by them. He is also shown to care about humans, particularly his vessels.

Soma's clan, the Day Breakers, have announced that there are indications in the lands of the Kingdom of Ishmael of the King's return.

History
His origins are unclear, as he claims to have become life after a long process of trial and error. Merry also refers to him as a rat.

His first vessel was Enad George, the founding King of Arabakia, so the two are often considered one and the same, though their interests did not completely align.

The second vessel was an orc named Diha Gatt. The third one, Itsunaga, was a man from the Hidden Village who was exiled and became a bandit. The fourth vessel was a mage called Yasuma. The fifth, a volunteer soldier called Ageha. The sixth vessel was Jessie Smith, and the seventh and last vessel, Merry. After Merry asks for his help in desperation, the No-Life King is able to gain control over her body.

Undead
According to Honen, Undeads are the result of any corpse that is not properly cremated within three days. Dark spells are less effective on them, they are resistant to physical damage, and will continue to fight until they are hit by Dispel.