Unversed

The Unversed are considered "the opposite of human life" and grow from the negative emotions produced when Chernabog gained the power to remove his emotions and make them into monsters for him to control. By all accounts, the Unversed are extensions of Chernabog, himself. They have not appeared in the Spongebob adventures series yet, but since Fagin is able to summon Heartless and Nobodies, he may be able to control the Unversed somehow.