Wolverine is the best there is at what he does, but he definitely hasn't had an easy go of things. Wolverine's time in the superhero community has been difficult for him. For years, Wolverine has been blindsided by some terrible secrets, ones that had a detrimental effect on his life.

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Wolverine is as tough as they come, but there are some things that take him out at the knees. Secrets have long defined Wolverine's life. Sometimes, it was things kept from him. Others, it was things he kept from people. Secrets can be poisonous and even Wolverine's healing factor can't save him from the fallout some secrets create.

10 Wolverine Found Out Onslaught Was Basically His Fault

An image of Wolverine and Electra watching Xavier and Magneto battle each other

Wolverine having his adamantium skeleton ripped out by Magneto was a catastrophic moment for him, but also for the Marvel Universe. In retaliation, Xavier mindwiped his old friend Magneto, an act that planted the seeds for Onslaught. Onslaught's attack wrecked the X-Men and put New York City under siege from reprogrammed Sentinels.

Wolverine and Elektra hunted down Gateway for help, and the mutant showed them things from their pasts. One of those things was what happened to Xavier when he mindwiped Magneto. If Wolverine had killed Magneto, Xavier wouldn't have had a reason to take revenge on the Master of Magnetism, sparing the world from Onslaught.

9 The Mongrels Were Wolverine's Secret Children

An image of The Mongrels preparing to fight, their weapons drawn

Wolverine has a lot of enemies. He's been around for a long time, and there are many people and organizations who want him dead, including a group called the Red Right Hand. They set out to destroy Wolverine and almost succeeded. They threw a lot at him, including the Mongrels. The mercenary group went at Wolverine hard, but he was able to kill them.

However, those murders came back to haunt Wolverine. When he finally confronted the Red Right Hand, he learned the truth about the Mongrels. They were his illegitimate children who all hated him because of his absence. Even though Wolverine won, he still lost.

8 Romulus's Manipulation Played A Huge Part In Wolverine's Life

Romulus displays his many claws in Marvel Comics

Wolverine is used to shadowy manipulators in his life, but he didn't know many of the tragedies he'd experienced had been orchestrated by one man. Romulus had been manipulating Wolverine's family for generations. Wolverine himself had worked with him before joining Weapon X and was a willing part of the ancient mutant's plans.

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Romulus gave the order to Weapon X to wipe Wolverine's memories, dooming Logan to years of searching. He and Romulus clashed many times, but Wolverine finally got a measure of revenge against him.

7 The Secrets Of Wolverine's Past Revealed His History As A Howlett

James Howlett, the boy who becomes Wolverine, in Wolverine: Origins

House Of M had many consequences, one of which affected Wolverine greatly. While mutants the world over lost their powers, Wolverine was seemingly given a gift. His memories were restored to him, but this was a double-edged sword. It allowed him to go on a journey of discovery, but it also revealed tragedies he'd known nothing about.

For example, Wolverine remembered his life as James Howlett. That meant that he finally remembered his family and childhood but he also remembered accidentally killing his mother. He remembered watching Rose, the woman he loved, fall in love with someone else and then die at that man's hands while he was fighting his half-brother, Dog Logan. It opened up wounds he didn't even know he had.

6 Wolverine's Secret Tenure In X-Force Angered His Fellow X-Men

Uncanny X-Force cover with Wolverine, Psylocke, and Deadpool

Wolverine's willing to do things that other heroes won't. After M-Day and the X-Men's move to San Francisco, Cyclops came to him with an idea. Wolverine was to assemble a secret team of like-minded mutants and hunt down threats to the mutant race before they attacked. It was a highly successful endeavor, but once the truth was out, Cyclops and Wolverine disbanded it.

However, Wolverine kept X-Force going. He recruited a new team and based them far away from Utopia. Even after his schism with Cyclops and the founding of the Jean Grey School, he kept X-Force operational. However, the faculty of his school learned the truth about X-Force and felt hurt by his lies.

5 Wolverine's Secrets Made The Avengers Unity Squad Vulnerable

The Uncanny Avengers, with Thor, , Captain America, Scarlet Witch, Wolverine in Marvel Comics

Wolverine has joined every major team in the Marvel Universe. After Avengers Vs. X-Men, Wolverine became a part of the Avengers Unity Squad. The team became enmeshed in the machinations of Kang and the Apocalypse Twins. The recent difficulties between mutants and the Avengers made things hard for the team, and the Apocalypse Twins took advantage of the opportunity.

The Avengers learned Wolverine had been running bloody X-Force missions while he was an Avenger. Even worse, they found out he had killed his son, Daken. This widened the rift in the team and made it easier for the Apocalypse Twins to enact their terrible plan.

4 Weapon X's Secrets Had A Lasting Effect

Wolverine wakes up as Weapon X in X-Men comics

Wolverine is Weapon X's most dangerous creation. The program gave him his adamantium skeleton, but that wasn't all. For years, Wolverine had a set of false memories. He remembered living in a cabin in the woods with a Native American woman named Silver Fox. He remembered Sabretooth killing her. He remembered missions and wars.

However, Wolverine discovered it was all a lie. Weapon X had created those memories for him, used memory implants, and blocked his old, true memories. The revelation that much of his past was a lie had a huge effect on Wolverine.

3 The Truth Behind Wolverine's Mutation Showed Just How Important His Adamantium Truly Was

Wolverine in a feral state, growling from the shadows in Marvel Comics

Wolverine's amazing adventures have taken him to strange places, but his feral period is one of his weirdest. After losing adamantium, he had to relearn how to fight and his healing factor was weakened for a time because of the strain on his system. Losing his adamantium also had an unexpected effect.

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After returning to the X-Men, he learned the adamantium had done more than give him unbreakable bones. The adamantium held back his mutation, keeping him from turning into an animal. Without adamantium, his mutation was moving at an alarming rate. Wolverine almost received new adamantium from the villain Genesis, but he expelled it to save Cannonball and became a more bestial version of himself.

2 Learning About The Existence Of Akihiro Placed Wolverine On A Collision Course With His Son

An image of Wolverine fighting his son Daken in Marvel Comics

Wolverine wasn't always the best father, and his children paid for it. Before he battled the Mongrels, he learned about his son Akihiro. While Wolverine was away on a mission, the Winter Soldier killed Logan's wife, Itsu, after which Romulus stole Akihiro away. Akihiro was left with a Japanese family and later trained to become an assassin.

Harboring rage against his father, Akihiro worked with Romulus against Wolverine. The two battled back and forth for ages, with Akihiro creating his own Brotherhood and going after Logan. Wolverine ended up drowning his son, an action that had major repercussions and haunted Wolverine for years to come.

1 Discovering He Had Bone Claws Made Wolverine Leave The X-Men

Wolverine popping out his bone claws in comics

Immediately after losing his adamantium and healing, Wolverine went into the Danger Room to prove he hadn't lost his edge. He went up against two combat robots and received brutal wounds because he was used to fighting with his missing claws. Suddenly, razor-sharp bone claws ripped through the backs of his hands.

This kicked off Wolverine's bone-claw era. Afraid that his breakable claws made him a liability to the X-Men, he left the team in the dead of the night. Wolverine needed to prove to himself that he could still be a hero without the adamantium skeleton and claws, and didn't want to endanger his friends.

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