A judge in Waukesha County, Wis., told the suspect standing before her that she had never seen a complaint as "horrific" as the one filed against him.
He is charged with 12 felonies after he allegedly posed as a girl online to trick male classmates into sending him nude pictures of themselves.
According to a criminal complaint, he then allegedly blackmailed some of them into committing sexual acts.
Stancl is charged with five counts of child enticement, two counts of second degree sexual assault, two counts of third degree sexual assault, possession of child pornography, the repeated sexual assault of the same child, and making a bomb threat.
"Mr. Stancl used the Internet to first communicate with people on Facebook, pretending to be a female," said Waukesha County District Attorney Brad Schimel. "After some conversations with these individuals, he would eventually coax them into providing him with nude photographs of themselves in exchange for what they thought was nude photographs of the girl they were talking with.
"It wasn't a girl, it was Anthony Stancl."
He allegedly exchanged pictures with at least 31 teenage boys, and Stancl then tried to blackmail or extort half of them into meeting him for sex acts.
"They were coerced into acts they didn't wish to be involved in," Schlimel said. "Stancl told them that if they didn't, he would show the pictures to all of their friends.
"All told, there were approximately 300 photographs of known New Berlin high school students.
There were over 600 other movies that were commercially produced -- child pornography videos --that had been downloaded off the Internet."
Stancl has no prior criminal record, and investigators believe he was working alone.
His alleged victims range in age from 13 to 19, and it's believed that additional victims have not yet come forward.
They are encouraged to contact the New Berlin Police Department.