- Broken Base: Some fans are not exactly thrilled to have another Joker story after his handling on the Death of the Family arc, especially because this one aims to top that one in terms of "making The Joker a threat" escalation. On the other hand, some fans like that it's the Joker and also like several scenes that have been spread throughout (such as the Batman Vs. Joker-ized Justice League sequence or the fact that he's such a hard-core threat that all of Batman's rogues' gallery are willing to band with Batman if they are to have a chance in Hell of beating the damn clown).
- Complete Monster: Finally deciding to kill Batman for real, The Joker creates a new Joker Venom and infects the entire Justice League with it, making them extremely aggressive and have them attack Batman as a distraction, before using the same toxin on all of Gotham. Joker plans to burn down the entire city as Batman tries to stop him, showing again and again that no crime is too awful for the Joker to get his laughs.
- Crazy Awesome: Joker's parade floats complete with the Batcave's T-Rex that the Joker steals amongst other trophies and puts in Joker make-up.
- Ho Yay: Ramped up in the final brawl between Batman and Joker. Capullo admitted to being intentional with some of the angles as well as making the blood pool between the two form a broken heart.
- Like You Would Really Do It: Bruce Wayne's supposed death. Scott Snyder has already mentioned that he'll come back after the entire Bat-Cop storyline is done and was even advised by Dan Slott to do this and let the fans get angry. As it later appears, it's zig-zagged; while Bruce actually did die, he was revived by the dionesium. However, he also lost all of his memories and knowledge of his training in the process, and is now working in the Narrows to aid the survivors of the Endgame there. While Alfred initially tried to get him to come back, he changed his mind later.
- Narm: For some reason, Batman's protective mask against the Joker toxin doesn't completely cover his lower face. When he screams, it makes it look like he has a mirror for a mustache.
- Nightmare Fuel: Metric tons:
- Jokerized Justice League members, especially Superman. What makes it creepier is that their grinning clown faces don't appear until long after the toxin has already turned them homicidal, making it appear that they just went crazy on their own. Wonder Woman even states that she's always hated Batman and just hasn't gotten around to killing him until now.
- After the teasing of it in Death of the Family, it's revealed the Joker DOES hide under Jim Gordon's bed. And his bluff about know Batman's real identity? Not a bluff after all.
- The effects of the new Joker toxin, now a virus that transforms Gotham into a kind of Laughing Mad Zombie Apocalypse.
- The page of Joker slowly swimming towards the Batcave entrance. Jesus.
- Older Than They Think: This isn't the first time Crazy Quilt has been Darker and Edgier - back in the 1980's, he nearly beat Jason Todd to death.
- They Copied It, So It Sucks!: One of the biggest complaints about this storyline is that it hits the same highlights as Death of the Family ( Joker scaring everybody (this time by making them believe that he's immortal or even a demon), dispersing Joker Venom in a fashion that infects many people in Gotham (this time as a virus), having people that Batman cares about Jokerised and used as weapons against him (this time by infecting the Justice League), invading the Batcave, doing all of this out of a Ho Yay sense of Woman Scorned (and being It's All About Me, deciding to wreck all of Gotham because he's essentially pulling one hell of a Rage Quit), being pretty much unstoppable for a good chunk of the story (this time because he lucked into some of the raw element that makes the Lazarus Pits, giving him a powerful healing factor, which helps with the aforementioned attempt to make people he's a demon)...), only difference is the writers trying to make things go Up to Eleven.
- They Wasted a Perfectly Good Plot: The Joker being a potential Eldritch Abomination? How is that not an amazing thing!? Wouldn't that have completely justified his Joker Immunity, his sick inhumanity? Wouldn't that be great!? But turns out he just got Lazarus Pit water...
- Sure, a supernatural Joker would have been a huge Base Breaker for replacing the powerless but brilliant maniac version. Except not too long after this story was published, DC revealed there were three Jokers running around, meaning both version could exist.
- The Woobie: Dr. Mareen Zaheer who simply commits the sin of trying to understand the Joker, is made completely into a fool by Joker's Border alias who tells her an entirely plausible but most likely false story of who the Joker is. As she learns the deception, her whole life's work a lie, she eventually ends her part in the story with a gun with six bullets and five Jokerized Arkham patients (who are all tricked into believing their individual story is the true Joker origin despite Zaheer's protests) looking to rip her to shreds. Her ending is sadly ambiguous on whether she's firing at the patients or herself or both.
YMMV / Batman: Endgame