The Casket Match may rank No. 8 on WWE.com's List of Most Extreme Matches, but it's the final word for those who are sealed within the coffin's mortal confines. The objective is quite literally an open-and-shut case: beat your opponent senseless, force them completely into an oversized casket situated at ringside, then close the lid before they get out.

Despite the otherwise easy concept, Casket Matches are not to be taken lightly. They're sanctioned only under grave circumstances, when the traditional pinfall or submission simply isn't enough for combatants to lay their rivalries to rest. Once that oversized pine box is brought to ringside, anything and everything goes; do whatever it takes to trap your adversary inside…or the last thing you'll see is the coffin lid closing down on you.

Without question, Undertaker is the squared circle's top tomb-rater. It was he who introduced World Wrestling Entertainment to the Casket Match (then called a Coffin Match) in November 1992's Survivor Series, when he hammered down the final nail in his conflict with Kamala. He also came out on the proverbial top of WWE's last documented coffined classic, barely besting Big Show at Survivor Series in November 2008. Yet not even The Phenom is perfect in a specialty match that's tailor-made for him. An army of Superstars helped then-WWE Champion Yokozuna plant him six feet (and 10-and-a-half inches) under at Royal Rumble 1994, while Kane, after ensuring that Shawn Michaels retained his WWE Title at Royal Rumble 1998, set the casket on fire…with Undertaker still inside.

It's only fair to note that being laid out on the coffin's exterior can be as devastating an experience as feeling the cold interior lining on your back. Despite emerging triumphant in a Casket Match with Undertaker in January 1998, HBK landed on the edge of the wooden sarcophagus, suffering a severe back injury that would force him into retirement for more than four years. While even that may sound more desirable than the obvious alternative, take our word for it: those who have endured the debilitating effects of a Casket Match do anything but rest in peace.