In this task, you are given a text of many news articles seperated by special token "|||||". Your task is to summarize them.

Just in time for Halloween, Burger King is releasing a special-edition sandwich that is not for the faint of heart. 
  
 The “Nightmare King” features a green bun, a quarter-pound of beef, a crispy chicken fillet, melted American cheese, thick-cut bacon, mayonnaise and onions on a glazed green sesame seed bun. 
  
 Get push notifications with news, features and more. 
  
 In a new online advertisement for the sandwich (below), the fast food brand claims to have partnered with Paramount Trials and Florida Sleep & Neuro Diagnostic Services, Inc. to conduct a scientific study over ten nights with 100 participants. After eating the new burger, they allege, the incidence of nightmares increased by 3.5 times, according to the results. 
  
 RELATED: Pasta Nachos! Churro Milkshakes! These Are Our Favorite New Menu Items at Chain Restaurants 
  
 RELATED: This N.Y.C. Restaurant Has a Halloween Menu Where Everything Is Made with Pop-Tarts 
  
 In the clip, people are asked to eat the burger before going to bed and then they’re hooked up to a sleep monitoring machine for the night. 
  
 “I remember hearing voices and people walking around talking,” one test subject says. “When I would wake up I think I didn’t hear the voices.” 
  
 RELATED VIDEO: This 100-lb. Mom of Four Just Set an Insane Burger Eating World Record 
  
 Another person says: “Someone in my dream turned into the burger. The burger then transformed into the figure of a snake.” 
  
 You, too, can enjoy the burger, with a side of nightmares, for $6.39 starting on Oct. 22. In celebration of the new menu item, Postmates will offer free delivery when you purchase it between Oct. 22 and Oct. 25. ||||| Published on Oct 16, 2018 
  
 Can a burger actually give you nightmares? 
  
  
  
 That’s what the BURGER KING® brand set out to prove with an unusual research study for its latest Halloween limited time offer, called the Nightmare King. Based on the unique build of the sandwich, which consists of a mix of proteins like bacon, chicken and beef, plus cheese, the hypothesis was that this new burger could cause nightmares. So, the BURGER KING® brand turned to science to validate this. And the results of the clinical study prove that the Nightmare King increases your chances of having nightmares by 3.5 times. 
  
  
  
 Caution: proceed at your own risk. 
  
 You’ve been warned. 
  
  
  
 Only at select participating restaurants. 
  
 TM & © 2018 Burger King Corporation. All rights reserved. ||||| CLOSE America's fastest drive-thru chain of 2018 will not only shock you, but probably cause a fight among friends. Nathan Rousseau Smith has the results. Buzz60 
  
 Burger King has a new sandwich for Halloween. (Photo: Burger King) 
  
 Burger King says its new sandwich is "clinically proven to induce nightmares." 
  
 In time for Halloween, the fast-food chain's "Nightmare King" is 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.” 
  
 More: Starbucks scares up new 'Witch's Brew Frappuccino' for Halloween 
  
 More: Best October deals: Your guide to this month's spooky specials and freebies 
  
 More: Taco Bell brings back its World Series' 'Steal a Base, Steal a Taco' promotion 
  
 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. Through 11:59 p.m. Nov. 1, get free delivery from Postmates where available with promo code "beroyal." 
  
 For a past Halloween creation, Burger King released a Halloween Whopper with a black bun. 
  
 For a limited time, Burger King has a Scary Black Cherry-flavored Frozen Fanta. (Photo: Burger King) 
  
 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. — Ashley Cefali (@BigCef1) October 9, 2018 
  
 The color of something else may also be changed, another Twitter user reported. 
  
 Burger King is now selling a "Scary Black Cherry" slush. Unfortunately, it turns your poop a very weird colour. #BlackPooppic.twitter.com/AjFcWLWDGF — Mark McKenzie (@89XMorningX) October 12, 2018 
  
 More: 6 best Halloween costumes for kids, families in 2018 from 'The Incredibles' to 'Boss Baby' 
  
 More: Halloween food ideas: Monster cake pops, jack o' lantern peppers and more party recipes 
  
 More: Sigh ... You can be a sexy Duchess Meghan for Halloween with this royal wedding costume 
  
 Kelly Tyko is a consumer columnist and retail reporter for Treasure Coast Newspapers and TCPalm.com, part of the USA TODAY NETWORK. Read her Bargainista tips at TCPalm.com/Bargainista, follow her on Twitter @KellyTyko and email her at kelly.tyko@tcpalm.com. Sign up for her weekly newsletter at www.tcpalm.com/newsletters. 
  
 Read or Share this story: https://www.usatoday.com/story/money/2018/10/17/burger-king-nightmare-king-halloween/1661125002/ |||||
The "Nightmare King" isn't just a seasonal name thrown on Burger King's latest burger. The quarter-pound beef burger topped with chicken, cheese, bacon, onions, and mayo, on a green sesame seed bun, is "clinically proven to induce nightmares," according to the burger chain. A new ad shows participants hooked up to sleep monitoring machines after eating the burger. Per USA Today, the incidence of nightmares increased 3.5 times over the normal rate, apparently due to various proteins. "I remember hearing voices and people walking around talking," one participant says, per People. The burger will be available for $6.39 from Oct. 22 through Nov. 1. (Burger King previously tried a black bun.)