Even though Billy Batson and the Magic of Shazam was generally an all-ages, Lighter and Softer take on Captain Marvel and the Marvel Family, its version of Freddy Freeman was darker than any other continuity's. Instead of suffering from partial paralysis, he's a complete paraplegic; and since Freddy's spine was broken by a building that Captain Marvel imploded, he hates Billy and Mary, and blames them for his injuries. This is a far cry from the original Freddy, whose spine was broken by Captain Nazi, who idolized Captain Marvel for saving his life, and who generally managed to have a fairly upbeat attitude despite his troubles.
DC's Post-Crisis universe got so grim, what with the Multiverse dying, Jason Todd being bludgeoned to death, Barbara Gordon getting shot through her spine by the Joker and paralyzed, Superman dying, Batman getting his back broken, Hal Jordan becoming evil courtesy of Parallax, Aquaman getting maimed... it drove Bronze Age character Superboy-Prime crazy — causing him to become a mass-murdering fanatic in Infinite Crisis. Superboy-Prime going mad was followed by an even darker storyline called 52, and also saw the relaunching of numerous series with a generally darker tone. A prime example is Checkmate; issue #1 featured a team of superpowered spies infiltrating a Kobra base and leaving no survivors (with the badass heroine of the series, Sasha Bordeaux, shooting the Kobra Big Bad dead, execution style). The series muted its violence considerably after the first half-dozen issues.
The New 52 reboot saw this taken Up to Eleven. Heroes got newer costumes that were more armoured and 'cinematic', as well as grimmer, more dour personalities. Fun elements like the Flash Family or Justice Society of America were Exiled from Continuity and certain Legacy Character heroes were reverted to their silver age selves, who were written as much more serious and grim figures. Heroes also lost their marriages and had their romantic histories erased, as it was believed by those Running the Asylum that "heroes are too damaged to get married". This goes further in some books than others.
Blue Beetle was originally a fun book that didn't take itself too seriously — for example, the scarab was played as a Heroic Comedic Sociopath. In the New 52, it was initially just a sociopath, and Jaime couldn't rein it in as much as he used to at first.
A literal version shows in Teen Titans, with the character Solstice. Prior to the New 52, she was a cheerful girl with light powers. Afterwards, she had a permanently inhuman appearance and shadow powers. In addition, Kid Flash has become a murderous rebel leader from the future, Raven is secretly working for her demon father, Wonder Girl is now a thief who gets her powers from an Artifact of Doom, and Superboy is the clone of Superman and Lois Lane's evil son from the future — though in his own series, the latter became very much a traditional hero.
Wonder Woman's increasing willingness to kill since her aforementioned offing of Maxwell Lord reaches an extreme with her becoming a proud warrior who casually and proudly murders criminals and boasting about it. This was especially jarring given attempts to hang onto her status as an All-Loving Hero, which dates back to the days when she was the DC hero most consistently and vocally opposed to killing.
Batgirl (2011) saw Barbara Gordon returned to the mantle, but rather than follow in the steps of how she was in the Silver Age, Barbara's story was grim. The Killing Joke was kept canon, and it was used to define every aspect of Barbara's story, with her suffering from PTSD and the recovery and development she made as Oracle after the event completely retconned from her character history. She also faced several villains who took being dark and edgy to an art form, and was regularly and constantly tortured. Notably, this was all mandated by Executive Meddling; Gail Simonewanted to write a lighter and softer take, but was told repeatedly by her editor to make the story grittier until she eventually left (at which point, the editor was changed and the new creative team launched the Lighter and Softer "Burnside" relaunch of the book). To hammer things home, the previous Batgirl run staring Stephanie Brown as the titular character was a critical and commercial success in large part because it was focused on being a light, idealistic book about bringing hope to a grim setting, so the grittiness of Simone's run stood out even more.
This ultimately is brought in for a Deconstruction, courtesy of Geoff Johns and DC Universe: Rebirth #1, who shows that no one likes a world filled with Darker and Edgier ideas, especially when it's the heroes who are hit with this. This is driven home with the revelation that Dr. Manhattan of Watchmen is the cause of all of this, having turned the pre-Flashpoint universe into the New 52 universe and seems utterly confused as to why it isn't working. It also serves as a Take That! to those who use the spoilered title as a manifesto to writing comics and not getting the message it was giving out.
DC's Vertigo imprint revolves around material intended for mature audiences. After the success of Swamp Thing, Doom Patrol, Hellblazer, Shade, the Changing Man, and Animal Man, all of which starred fairly obscure characters from established DC canon, up to and including a brooding, psychological take on Brother Power The Geek. For the uninitiated, Brother Power is a human-sized hippie rag doll given life and super strength by magic sunshine who once ran for a U.S. congressional seat and was last seen orbiting the Earth.
Grant Morrison's Kid Eternity is a particularly archetypal example: Kid Eternity was originally a boy who died with his grandpa due to a clerical error in Heaven and was brought back to life with the power to summon any figure from history to help him. Morrison's version reveals that his "grandpa" was an unrelated pedophile he was caught up with, the entire "clerical error in Heaven" story was a fabricated scenario created by cosmic beings of Chaos so they could use the Kid as a pawn against cosmic beings of Order, and the "figures from history" were actually demons from hell that could shapeshift into whatever the Kid wanted.
The Earth One line plays it very straight, however, as among other things, Bruce Wayne isn't as skilled as other versions and is originally solely about bringing in the man he believes had his parents killed to justice, Alfred is the family's bodyguard (not their butler) and encourages Bruce to kill, Jim Gordon is a reluctant Dirty Cop, Diana is a Child by Rape between Hercules and Hippolyta and Hippolyta originally kept Diana for the purpose to enact a war against all males, Starfire is the source of several Titans' powers thanks to STAR Labs (led by Cyborg's villianous mother) experimenting on them, the Green Lantern Corps is already gone by the time Hal Jordan gets his power ring — though things improve on that end thanks to Hal, Hal himself is more jaded and cynical, and the last Guardian is insane.
The Flintstones, while still basically The Flintstones, features a lot more adult humor and storylines than what would be allowed in the 1960s cartoon. For example, Fred Flintstone and Barney Rubble are Shell Shocked Veterans, and in one issue Fred and Wilma are ostracized for practicing monogamy. Despite the more adult themes, the comic has a lot of heart, such as the topic of gay marriages (non-breeding pairs aided others in Fred's tribe).
In 1959's Action Comics #252, Supergirl lands on Earth and is found by her cousin who sees that she is being taken care of (even if his methods are questionable). In contrast, Kara Zor-El's 2004 The Supergirl from Krypton origin involves kryptonite meteors, fanservice, a paranoiac Batman and Darkseid kidnapping her and brainwashing her. On the plus side, Superman immediately wanted to take his cousin in and introduce her to Lois.
At the beginning Kara was a naive, innocent, sweet newcomer. However she grows up during the Silver and Bronze Ages, and although she never stops being an idealistic hero, her childlike innocence goes away. This is made clear in Adventure Comics #424, in where she wears sexy clothes while trying to get a scoop.
When Supergirl was rebooted in the Post-Crisis continuity, several writers and editors thought the best way to update the character was turning her into a mood-swinger, self-centered, bratty jerkass. This strategy continued until DC realized that Supergirl's fans hated it. Supergirl's earlier characterization was retconned out and she became a troubled, insecure but ultimately good and heroic teenager again.
Post-Flashpoint Supergirl started out this way, with Kara being a reluctant hero at best, traumatised and, like most teenagers would under her circumstances, feeling overwhelmed and simply wanting to go home. She also holds a fairly dim view of humanity at large, but considering that they keep shooting at her and have poisoned the atmosphere with Kryptonite. Grief morphed to rage, partly under the influence of being manipulated and betrayed by H'el, and she became a Red Lantern for a little bit. Now, however, she's discarded the Red Lantern Ring, has come to terms with her losses, matured and become that much wiser. She has since accepted Superman's charge to be Earth's hero in his stead in The Final Days of Superman and Supergirl (Rebirth).
Superman: Earth One was explicitly advertised as being darker, sexier, and moodier, and many standard elements of Superman's story are given a darker spin — for example, Jonathan and Martha are forced to keep Kal-El a secret after government agents secretly impound his spaceship in a secret base, Krypton's destruction was a deliberate act of war, and Superman's more angsty than other portrayals and is distrusted by the public... but despite that, there remains a core of hope, with Clark realising that the people of Earth had a reason to be afraid (after that fear was exploited by Zod (here, Zod-El, Superman's uncle)), and comes to something of an accommodation with the United Nations.
Superman: Red Son: A "what if" story showing what would happen if baby Kal-Lel landed in Soviet Russia instead of Smallville. The result? A communist empire led by the world's strongest man, with all of Clark's desire to change the world for the better, but with a misguided worldview, and none of his respect for free will.
The Revolutionary War hero Tomahawk received a pretty good Vertigo reimagining in Vertigo Visions: Tomahawk.