#4. The Chamber has only been invaded once
Elimination Chamber is quite a solid structure, which means that much like Hell in a Cell, it is quite hard to break inside. The doors are chained shut when all superstars are in the match and are only opened when a superstar is eliminated.
It seems that The Wyatt Family are the only stars who have ever been able to breach the Chamber when they attacked John Cena and Daniel Bryan back at Elimination Chamber 2014 to set up a match between Cena and Wyatt at WrestleMania.
With all the rumours circulating about a match between Undertaker and Cena at this year's WrestleMania, it will be interesting to see if The Undertaker decides to invade the Chamber and cost Cena his chance to fight Lesnar and main event The Grandest Stage Of Them All once again.