Stank (magic)

"Centuries ago, a great war was waged between good and evil, between Ninja and Sorcerer, too powerful to destroy. The Dark One was locked deep underground, his prison sealed with a sacred stone. In the darkness he waits, wreaking havoc, possessing the vulnerable using that which they hold most dear, amassing power from chaos. Once he gains enough power, he will escape and darkness will reign. Preventing this is the sacred duty of the Ninja."

- Excerpt from the NinjaNomicon

Stank is a form of dark magic used by the Sorcerer in the Disney XD series Randy Cunningham: 9th Grade Ninja. It appears as a concentrated, chaotic mist that transforms people into violent, aggressive monsters.