Gotham City Councilman Thomas Hart, better known as Nicodemus, made his only appearance in a two part story in 2002's Batman #601-602. Witnessing his parents murdered at a young age, young Thomas Hart didn't have the Wayne family fortune to fall back on. The corrupt and underfunded Gotham City foster system did little to reduce his rage. Indeed left to stew, the young Nicodemus reached a religious revelation: Gotham City was innately evil and must be destroyed. As a member of the city council, he was uniquely situated to stalk, kidnap, and kill the city employees he held responsible for his childhood. Nicodemus even faked his own kidnapping and allowed Batman to "rescue" him to distract attention away from himself. Ultimately though, Batman managed to put the pieces together and was able to stop him from blowing up City Hall. But not before Nicodemus was able to escape.
Let's start with the bad. Really I only have two complaints about Nicodemus. The first is with his design. While the stage magician fire from his hands and eyes is ominous and works well with his religious/hell motif, the rest of it isn't exactly memorable. He's shaved off all his body hair (presumably so he doesn't accidentally set it on fire) and wears a trench coat. Oh, and he has a weird turtleneck thing covering the lower half of his face. That's it. Admittedly it's a look that screams "this guy is not all there mentally", but it doesn't really scream supervillain until he sets himself on fire. The second problem with Nicodemus could probably be fixed if he ever appeared again. Simply put, how and why exactly did a mentally ill kid become a City Councilman. I mean the how can probably be glossed over by saying "politician" and "Gotham City," but why upon deciding that Gotham City was innately evil did Nicodemus then say "I should run for the City Council." It's not like any other supervillain has needed to get themselves appointed to the Architectural Review Board before they could kidnap the mayor and try to destroy Gotham City. Maybe he was trying to save the city before he decided it was beyond redemption, or maybe he had some more sinister reason, but there should be some explanation.
But the rest of Nicodemus is pretty great. While the idea of a dark mirror to Batman's origin story isn't exactly new, normally it takes the form of the child of criminals who were gunned down by the police or some such. The only fundamental difference between Thomas Hart and Bruce Wayne is that Bruce had money and a support network, while the young Nicodemus was left truly alone, allowing his anger to consume him. Indeed, because their origins are so similar, Nicodemus doesn't actual view Batman as an enemy, but merely a noble soul trying to save a city that is beyond redemption. Not only is it nice to have more Batman villains who are thematically related to him without having to be personally obsessed with him, but that relationship is essentially the plot of 2005's Batman Begins (which can almost never be a bad thing). On top of that, hell and brimstone patter combined with fire imagery pretty easily adds up to a good Batman adventure. Finally, Nicodemus did promise to return, and it really would be a shame for him to break his promise.