Burger King says its new sandwich is “clinically proven to induce nightmares.”

In time for Halloween, the fast-food chain releases its “Nightmare King” on Monday, which will be available through Nov. 1 at participating locations nationwide.

This “spooky sandwich” features a quarter pound of flame-grilled beef, a white meat crispy chicken fillet, melted American cheese, thick-cut bacon, creamy mayonnaise and onions on a glazed green sesame seed bun. Yes, a green bun.

Burger King says it put the burger to the test and worked with the Paramount Trials and Florida Sleep & Neuro Diagnostic Services to conduct a sleep study.

According to a news release, they conducted “a scientific study over 10 nights with 100 participants (or should we say victims?) who ate the Nightmare King before they went to bed.’

Doctors and scientists identified whether the individuals had vivid dreams by tracking various signals from the sleeping subjects including their heart rate, brain activity and breath.

“According to previous studies, 4 percent of the population experiences nightmares in any given night,’ said Dr. Jose Gabriel Medina, the study’s lead doctor, in a statement. “But, after eating the Nightmare King, the data obtained from the study indicated that the incidence of nightmares increased by 3.5 times.’

The Nightmare King has a recommended price of $6.39, according to the company. From Oct. 22 to 25, get free delivery from Postmates where available with promo code “scarygood.”

For a past Halloween creation, Burger King released a Halloween Whopper with a black bun.

Scary drink?
Burger King has another frightening item available for a limited time – the Frozen Fanta Scary Black Cherry.

This might bring on nightmares after drinking.  Some Twitter users said it stained their mouth.Warning: Burger King’s Black Cherry Slushies DO stain your mouth black.

The color of something else may also be changed, another Twitter user reported.