We have heard of heroes and we have heard of anti-heroes. There are many instances when heroes have toed the line and turned into villains. Similarly, there are instances when villains have turned into heroes. What can one say, sometimes you see just light at the end of the tunnel? It makes one believe in redemption and the fact that no one is exempt from it. You may call them turncoats.

RELATED: Harley Quinn's Bat: 10 Of Her Favorite Weapons

Instances of comic book villains joining the forces of good are many. In each case, it's difficult to assuage what exactly drives these villains towards change. In some cases, they start bad and it only takes an accident to turn them into good humans, in other cases, they go back and forth. Every time a super-villain is born, gods flip a coin (you get the reference). Here are ten times villains turned into heroes in DC.

10 DEATHSTROKE

Deathstroke, aka Slade Wilson, is a merc with a reputation. He did serve in the U.S military for a considerable amount of time before they turned him into a lab rat, you know. Over the years, Deathstroke has actively turned to the good side, he had helped the Earth's heroes and the U.S. government to save the planet. He served in the U.S. government in the Vietnam war.

His contributions to the nation are many. He saved the human population from extinction in Deathstroke the Terminator Annual Vol 1 by single-handedly taking down the perpetrators named the Genetix, aka DNA aliens. Deathstroke's moral philosophy is pretty clear, he always believes in the 'greater good'.

9 RED HOOD

Red Hood, previously Jason Todd, has one of the most complicated storylines in all of DC. Jason Todd, who was Batman's side-kick, was killed by the Joker in the infamous Death In The Family story arc. You'd think DC would leave him alone after his death, but no, they decided to retcon him into Red Hood, undoubtedly the worst DC retcon. From Joker's puppet to a drug stealer, Red Hood has done it all.

Yet retcon after retcon, in the New 52, Red Hood formed his own group of Outlaws with sidekicks: Starfire and Arsenal to take down the criminals and violent thugs in Gotham. Not only did he mend his relationship with the Bat, but he also embraced Batman by wearing his Bat symbol on his outfit.

8 THE PIED PIPER

Pied Piper plays his flute - musical comic characters

Hartley Rathaway, aka The Pied Piper, has been a formidable enemy of The Flash. He made his first appearance in The Flash #106 (1959). Born deaf to incredibly rich parents, Hartley fell in love with sound once he received hearing implants. He began experimenting with different sounds, to the extent that he gained powers to hypnotize and create Sonic weapons.

Nevertheless, he has reformed and gone onto champion the cause of the underprivileged: the homeless of New York. He has also fed the homeless citizens and helped them obtain residence rights. He's befriended Wally West in the later stories and aided him in escapades with his vast knowledge. Additionally, he was one of the first DC characters to publically announce his homosexuality.

RELATED: The Flash: 10 Worst Things That Captain Cold Has Ever Done

7 TWO-FACE

Harvey Dent after re-scarring himself in Batman: Face the Face from DC Comics

Sometimes you miss the good old Harvey Dent. Before he was Two-Face, Harvey was Gotham's district attorney and Batman's bud. That was until Sal Boss Maroni threw acid on him causing him to literally become Two-Face. Batman has constantly put in efforts to reform his old bud, there are times when these efforts have proven fruitful.

In Batman: Hush, Two-Face underwent plastic surgery and turned into an older version of himself. He stepped into Batman's shoes and protected the city for him. Hence, Two-Face, like his physical form, has always had a diametrically opposed morality.

6 LEX LUTHOR

Ah Lex Luthor, the sadistic Führer of Metropolis. Superman's nemesis and a delusional being. Lex believes that he's a hero no matter what. As a result, he acted like a hero many times. Lex was instrumental in helping the League in the Darkseid War.

Lex joined the Justice League after aiding them in taking down the Crime Syndicate in Crisis on Two Earths: Crime Syndicate Earth. You will be delighted to know that Lex was the leader of the Justice League in the said story arc.

5 PLASTIC MAN

Not many have heard of Plastic Man, let alone knowing that he embraced piety. Plastic Man is a Golden Age superhero whose origin is almost similar to that of the Joker. Patrick Eel O'Brian started out as a thief to sustain himself and in a theft gone wrong, he fell into a vat of unidentified chemicals.

Only he didn't embrace insanity like the Joker. Instead, upon gaining shape-shifting superpowers, he joined the city police department to fight crime. What's more, he quickly rose through the ranks to become a full-time federal agent with the FBI. Plastic Man breaks bad every now and then but that doesn't diminish his contributions at work.

RELATED: 10 Key DC Characters Who Debuted In The ‘90s

4 CLAYFACE, THE FIRST

Clayface, aka Basil Karlo, was an actor who couldn't handle the inconsistency of the entertainment world. He was driven to the bad side in a fit of rage when he heard his film Dread Castle was being remade. He donned the mask of a character he once played, Clayface, to kill the actors.

You'll be amazed to learn that Clayface has turned to the good side in the recent Rebirth. Batman knocks some sense into him by showing him his pictures from his acting days. In Detective Comics 934, Karlo is recruited by Batman to join the new team of superheroes to fight crime, and offer which Karlo takes happily.

3 CATWOMAN

Yep, you heard it right. Catwoman wasn't always the vigilante hero and Batman's aid. Not that she was a supervillain or anything, she was just a thief. Not an ordinary one, her dexterity complemented by her agility and she traded blows with Batman regularly.

Fortunately, her heart always belonged to Batman. Therefore, by the 1950s, Catwoman was seen aiding Batman, instead of fistfighting him. Her love for Batman may have been her saving grace in countless instances, but like others in this list, she's always been a dilly-dally.

2 POISON IVY

Just like Harley Quinn, Poison Ivy's flame had tilted towards the other side of morality. She took to crime just so she could survive, leave Gotham behind and live with her plants on an Island. She was doing good until an American company obliterated her Island. Her character was tilted by writers Gail Simone and Stjepan Sejic in a future possibility of her get getting her own series.

In the All-Star Batman comics, Poison Ivy becomes a member of Birds of Prey and fights alongside Batman to defeat Clayface. She is best remembered as the villain who has traversed on either side of morality depending upon the situation.

1 HARLEY QUINN

And the top slot goes to the clown princess of Crime, Harley Quinn. If Harley can break bad and throw away her promising career as a psychologist to join the Joker, she can always turn to the good side. Case in point: she's the current leader of the Suicide Squad. Her chemistry with the anti-hero Deathstroke was particularly loved by fans. To think that Harley would break out of the vicious Joker romance and navigate her own.

Harley Quinn has always switched roles. In Injustice, she helped Batman take down the corrupt Superman. Remember the time she helped Amazon defeat Granny Goodness? There are times when she saved Batman's life. She once teamed up with the Looney Tunes to prevent the Joker from killing Batman. Recently Harley has come to be identifiable as an anti-heroine. We'll still say her morality is complicated.

NEXT: Deathstroke: His 10 Most Heroic Moments And 9 Most Villainous (And 1 Completely Unforgivable)