Nocturna

Nocturna is a villain in the Sidekick series, and is the main antagonist of Sleepless In Splitsboro. He has the ability to create nightmares and invade people's dreams.

History
He was once a former sleep scientist, who hoped to enter the dream world, but due to Maxum Man's shenanigans, he became trapped in the dream world. Seeking vengeance he invaded Maxum Man's dreams and created all sorts of nightmares for him, eventually forcing him to give up sleep.

He attacked the sidekicks' dreams as well, but they soon defeated him by thinking of happy dreams, which shrunk him to size.