The Joker has always had an uncanny ability to disguise himself when the situation calls for it. Despite his highly distinctive appearance and mannerisms, he's been able to hide even in plain sight when he needs to. The Joker has always figured out how to slip by Batman unnoticed, preferring it when his punchlines really come as a surprise.
But he may have never shown such a great aptitude for it as he did during Scott Snyder and Greg Capullo's New 52 run on Batman. As Eric Border, the villain spent a great deal of time befriending the Arkham staff, all in the pursuit of creating the perfect trap for Batman. Now, here's everything you need to know about the Joker's Eric Border persona and how he used it to torment the Dark Knight.
Schemes Inside Schemes
One of the Joker's most brutal plans led to him trying to eradicate all of the people he saw standing between himself and Batman, during "Death of the Family." However, his plans were thwarted by the united efforts of the Batman family. Bitter at Batman for rejecting his offers to "help," the Joker decided to bring down all of Gotham around him. Accordingly, the Joker went into hiding, with the Bat-Family unaware if he was alive or not. The Joker used this to his advantage, allowing Batman to become distracted with other threats while he set up his plans.
This gave Joker time to lay low, by assuming a quiet and simple persona. He went by unnoticed as a myriad other threats came to Gotham City, exactly like how he planned. Eric Border was everything the Joker wasn't, which is why it made for the perfect cover even when he was dealing with Batman.
How It Worked
The Eric Border persona was derived as a perfect joke to play on Batman. He came to the hero as a new orderly within Gotham. He helped the patients and seemed to be a good man. Using muscle relaxants, Joker was able to take away his distinctive smile and talk with a range of emotions. Meanwhile, he used specific makeup to completely hide his unnatural skin color. For all appearances, Eric was just another orderly at Arkham Asylum.
Even the name he chose was really just a prank on Batman. The first half of Eric, Ei, is proto-Norse for "eternal". Reicks stands for ancient Gothic, meaning "Prince". Border is a homophone for the word "Bourder". The word is an out-of-date phrase which translates into the modern lexicon as "Jester". So, by calling himself Eric Border, the Joker was announcing himself as something eternal, part of Joker's overall plan to convince Batman he was some ancient evil. He openly called himself a jester prince, which isn't far from his classic title of the Clown Prince of Crime. Joker was almost daring Batman to figure it out.
Joker's Endgame
With Batman completely unaware that the Joker was moving around Gotham, the Clown Prince of Crime was able to infect not just a majority of Gotham City with his toxins, but even the entire Justice League. While Batman was pressured by the rest of his fellow superheroes, Joker was able to silently begin the next phase of the plan, luring the superhero into the collapsed Arkham Asylum. Revealing his identity to Batman, Joker laughed as his plan went into action and almost wiped out all of Gotham City.
"Endgame" was one of the biggest Joker schemes ever, eventually leading to the Bat-Family teaming up with their villains to stop the Joker from outright destroying Gotham City. Although he ultimately lost, none of the Joker's plan would have been possible if he hadn't figured out the perfect way to slip by unnoticed even when the world's greatest detective is staring him down.