This Sunday, Dec. 15, the WWE presents its TLC: Tables, Ladders and Chairs pay-per-view event live from the Toyota Center in Houston, and there has been a lot of speculation as to the finish of the John Cena vs. Randy Orton title unification match as well as what the final card would be, and the WWE added a WWE Tag Team Championship match to Sunday's card at Tuesday's SmackDown tapings.

On this week's episode of SmackDown, it was revealed that the WWE Tag Champions Cody Rhodes and Goldust will defend their championships in a fatal four-way tag match against The Big Show and Rey Mysterio, Jack Swagger and Antonio Cesaro and Ryback and Curtis Axel. All four teams will go head-to-head with the tag belts up for grabs in what was announced as the seventh, and probably final, match for the card.

With Cena defending his World Heavyweight Championship up against Randy Orton's WWE Championship in a title unification tables, ladders and chairs match highlighting the show, backstage rumors last week indicated that there may be some sort of "screwy ending."

Wrestlingheadlines.com reported last week that speculation within the WWE was that the ending between Orton and Cena will not resolve the current problem within the WWE of having two champions and that after the match, there won't be just one champion emerging. The report indicated that with the WWE building up The Authority as "guaranteeing" that there will be a new champion, something fishy may go down at the pay-per-view.

One backstage report indicated that there is a possibility that the WWE may somehow have Orton and Cena switch titles, with Cena walking out with the WWE Championship while Orton escapes with the World Heavyweight Championship, possibly as a way to lead into a WrestleMania XXX title unification match for the two wrestlers, though it has also been rumored that Cena could be paired with a returning Hulk Hogan for a tag match at the event.

The WWE has always changed its plans, so it is possible that Cena or Orton emerge as the unified champion at TLC.

The card also has two 3-on-1 handicap matches pitting Daniel Bryan against Bray Wyatt, Luke Harper and Erick Rowan while CM Punk goes up against Roman Reigns, Dean Ambrose and Seth Rollins.

With the Intercontinental Championship on the line, Big E Langston defends against Damien Sandow on the card. A.J. Lee will also put her Divas Championship up against Natalya while Fandango and Dolph Ziggler go head-to-head on the TLC kick-off pre-show.

WWE TLC 2013 is the final pay-per-view of the year and takes place this Sunday, Dec. 15 live from the Toyota Center in Houston.