The Mexicanprofessional wrestling company Consejo Mundial de Lucha Libre has held a number of major shows over the years using the moniker Sin Piedad for a major show intermittently since 2000. The name has primarily been used for CMLL's "end of the year" show in December with one exception when the show was held in August. CMLL has on occasion used a different name for the end-of-year show, but Sin Piedad is the most commonly used name. All Sin Piedad shows have been held in Arena México in Mexico City, Mexico which is CMLL's main venue, its home base and main venue. The 2017 Sin Piedad was the second time such a show under that name was held on New Year's Day. Starting in 2011 through 2014 CMLL has been promoting a New Year's Day show with bigger, more prominent and promoted matches as part of the show although they did not specifically promote the shows under a special name, they were simply a special version of their weekly Saturday, Sunday, Tuesday and Wednesday shows that they hold in Arena Mexico on a regular basis. Starting in 2011 CMLL added at least one high-profile match to their shows, slowly building them into a special event. in 2011 the show featured the annual Reyes del Aire tournament, won by Ángel de Oro. In 2012 the January 1 show saw Hombre Bala Jr. and Super Halcón Jr. defeated the team known as Los Rayos Tapatío in a Luchas de Apuestas, masks vs masks match in what turned out to be Los Rayos last match in CMLL. The main event of the 2012 was the finals of a tournament for the vacant CMLL World Heavyweight Championship which was El Terrible defeat Rush 17th heavyweight champion. The 2013 start of the year show was highlighted first by then CMLL World Welterweight ChampionPólvora successfully defending against Titán and then the team of Boby Zavala and Disturbio defeated Leono and Tigre Blanco, forcing Leono and Blanco to have their hair shaved off as a result. The 2014 show, the last January 1 show without a specific title saw Super Halcón Jr. win that year's La Copa Junior tournament. Late in the show Mephisto defeated Atlantis to retain the Mexican National Light Heavyweight Championship in the main event. CMLL did not hold a show on January 1, 2015 but returned to the tradition in 2016 with Sin Piedad, that was streamed live online and later broadcast as part of CMLL's weekly television. the 2016 Sin Piedad featured two Luchas de Apuestas matches.
Storylines
The event featured five professional wrestling matches with different wrestlers involved in pre-existing scripted feuds, plots and storylines. Wrestlers were portrayed as either heels or faces as they followed a series of tension-building events, which culminated in a wrestling match or series of matches.
