Clancy

Clancy is a man who as the ability to control and order any type of insect species. He used to live at 8610 Chester Street, which is an abandoned apartment. When Councilwoman Liang attempts to redevelop the area, he learns that his residential area must be torn down to successfully finish the project. He decides to take action and had the intention to feed her to his insects, but Fourarms was able to come to the rescue. His plan to save his home fails, though the idea of destroying the whole city seems to satisfy his revenge towards them. He was stopped by Heatblast with abnormal abilities, but he decides to take revenge on them for ruining his plan to destroy the city. Luckily, Grandpa Max's San Ju Yen Pien medicine overrides Clancy's control over them, and Max delivers the final blow to knock him out once and for all.

Clancy is part of the Negative 10, although his appearance is drastically changed. He appears to be mutated into a buglike, Stinkfly-looking creature.

Appearences
Ben 10 vs. the Negative 10 (Part 1) / Ben 10 vs. the Negative 10 (Part 2)