Problem: Petra is a music group regarded as a pioneer of the Christian rock and contemporary Christian music genres. Formed in 1972, the band took its name from the Greek word for "rock". Though it disbanded formally in 2006, incarnations have played reunion shows in the years since and released an album in November 2010. In 2013, it reformed with a new drummer, Cristian Borneo, and recorded a new song titled "Holy is Your Name", before going back on tour.

The four band members and studio drummer Keith Edwards recorded Never Say Die and released it in 1981, with the first single a song originally written and performed by Volz's old band. "The Coloring Song" was Petra's big break, rocketing to the top of three Christian radio charts (rock, adult contemporary, inspirational) and reaching the top five of a fourth (southern gospel). Other songs - including the haunting "For Annie," the rocking "Chameleon" and the controversial "Killing My Old Man" - became audience favorites.  Sporting a heavier, more polished sound in the vein of Foreigner, Styx or Kansas, Never Say Die became the breakthrough album for which the band and its label had hoped, receiving rave reviews. CCM Magazine compared the band's new sound to Boston's, praising the album's lyrical and musical content and calling Never Say Die "by far their finest to date."  Ultimately, "The Coloring Song" became the third-hottest song on Christian radio in 1982 and the 14th-highest-ranked single of the decade on the Christian adult contemporary charts. It stayed on the radio charts an astounding 14 months, while "For Annie" reached the top five on Christian radio in 24 markets.  As important as the success on radio was the band's ability to tour nationally - the costs of which had been formidable in previous years. Unable to raise enough money for nationwide tours in support of its previous albums, Petra received another break when the band Servant invited it to open on its 1981-82 tour. Under Hollingsworth's tutelage, the band refined its live performances, its members dressing in camouflage to emphasize the spiritual warfare theme recalled by Never Say Die's artwork, which featured an ocean war setting with an electric guitar doubling as an aircraft carrier. The tour turned Never Say Die into a commercial hit. In December 1981, it became the first Petra album to crack the Billboard Top 40 Inspirational LPs chart, debuting at No. 27, peaking at No. 7 in April 1982, and lasting on the chart through February 1983, more than 60 weeks after its debut.

Did Petra bring in any guest singers for the Never Say Die album?

Answer with quotes: Petra received another break when the band Servant invited it to open on its 1981-82 tour.

Background: Captain Marvel, also known as Shazam (), is a fictional superhero appearing in American comic books published by DC Comics. Artist C. C. Beck and writer Bill Parker created the character in 1939. Captain Marvel first appeared in Whiz Comics #2 (cover-dated Feb. 1940), published by Fawcett Comics.
Context: After the success of National Comics' new superhero characters Superman and Batman, Fawcett Publications started its own comics division in 1939, recruiting writer Bill Parker to create several hero characters for the first title in their line, tentatively titled Flash Comics. Besides penning stories featuring Ibis the Invincible, Spy Smasher, Golden Arrow, Lance O'Casey, Scoop Smith, and Dan Dare for the new book, Parker also wrote a story about a team of six superheroes, each possessing a special power granted to them by a mythological figure.  Fawcett Comics' executive director Ralph Daigh decided it would be best to combine the team of six into one hero who would embody all six powers. Parker responded by creating a character he called "Captain Thunder". Staff artist Charles Clarence "C. C." Beck was recruited to design and illustrate Parker's story, rendering it in a direct, somewhat cartoony style that became his trademark. "When Bill Parker and I went to work on Fawcett's first comic book in late 1939, we both saw how poorly written and illustrated the superhero comic books were," Beck told an interviewer. "We decided to give our reader a real comic book, drawn in comic-strip style and telling an imaginative story, based not on the hackneyed formulas of the pulp magazine, but going back to the old folk-tales and myths of classic times".  The first issue of the comic book, printed as both Flash Comics #1 and Thrill Comics #1, had a low-print run in the fall of 1939 as an ashcan copy created for advertising and trademark purposes. Shortly after its printing, however, Fawcett found it could not trademark "Captain Thunder", "Flash Comics", or "Thrill Comics", because all three names were already in use. Consequently, the book was renamed Whiz Comics, and Fawcett artist Pete Costanza suggested changing Captain Thunder's name to "Captain Marvelous", which the editors shortened to "Captain Marvel". The word balloons in the story were re-lettered to label the hero of the main story as "Captain Marvel". Whiz Comics #2 (cover-dated Feb. 1940) was published in late 1939.
Question: Are there any other interesting aspects about this article?
Answer: The first issue of the comic book, printed as both Flash Comics #1 and Thrill Comics #1,

Question:
Hickenbottom was born on July 22, 1965 in Chandler, Arizona. The last of four children - Randy, Scott, and Shari are his older siblings - he was raised in a military family and spent a brief part of his early years in Reading, Berkshire, England, but grew up in San Antonio, Texas. As a child, Hickenbottom disliked the name Michael, so his family and friends just called him Shawn. Ever since, he has been referred to as Shawn.
On the December 14 Raw, Michaels won the Slammy Award for Moment of the Year for his match against The Undertaker at WrestleMania XXVI. Michaels accepted the award via satellite. Three days later, he announced a long-term deal with WWE, where he will serve in an ambassadorial role. He made his in-person TV return at the December 11 Tribute to the Troops taping, where he and Triple H had a one-night only DX reunion.  He appeared on the January 10, 2011 Raw, where he was announced as a WWE Hall of Fame class of 2011 inductee. After being ridiculed by Alberto Del Rio later that night, Michaels hit him with Sweet Chin Music. On the March 28 Raw, Michaels addressed Triple H and The Undertaker about their match at WrestleMania XXVII. Michaels was inducted into the WWE Hall of Fame on April 2 by Triple H. They were also joined by fellow Kliq members Kevin Nash (who had returned to WWE for the Royal Rumble) and Sean Waltman. He returned on the June 27 Raw, where he was confronted by CM Punk, and superkicked David Otunga and Michael McGillicutty. Later that night, when Diamond Dallas Page's special appearance was interrupted by Drew McIntyre, he superkicked McIntyre.  In June 2011, Jim Ross, Michaels and Hart announced that the three were working on a DVD chronicling the careers of Hart and Michaels that the WWE was planning to release in October 2011. The subject of the DVD would be their on-screen rivalry and real-life conflicts, with a particular focus on the Montreal screwjob. In his tweet, Hart described working on the DVD as a "cathartic" experience, and Ross asserted that both Hart and Michaels had been very honest and emotional in their interviews. The DVD, Shawn Michaels vs Bret Hart: WWE's Greatest Rivalries, was released in November 2011.
Answer this question using a quote from the text above:

what was the subject of the dvd?

Answer:
The subject of the DVD would be their on-screen rivalry and real-life conflicts, with a particular focus on the Montreal screwjob.