Because Marvel Comics' mutant superhero has a tough attitude and an unforgiving berserker rage, Wolverine has done some savage things to his X-Men teammates. With an uncontrollable fury, Wolverine, also known as Logan, has an instant desire for blood, which works best during his battles against super-villains. After being a loner for so many years, Logan hasn't aged well and has occasionally forgotten from time to time how to get along with others. There are certain members in the mutant superhero team who would rather Wolverine go back to his drinking, than deal with his bad temper and unfriendly personality.
During his full-fledged appearance in The Incredible Hulk #180, though he was small in stature, Bruce Banner immediately learned that Wolverine's retractable claws could cause an immense amount of damage. With his bones made up of an indestructible metal alloy named adamantium, Logan proved to be a worthy asset in the violent battlefield as a valuable superhero, soldier, and mercenary. Because of his mutant healing factor, Logan has survived through the worst injuries and resurrected after fatal headshots. Unfortunately, his healing factor cannot put together an already broken heart.
10 Killed Jubilee
In writer, Mark Millar's, and artist, Steve McNiven's, Wolverine: Old Man Logan, a group of 40 super-villains suddenly attacked the X-Mansion. The last of the super-villains, Bullseye, was the longest to take down until Wolverine snapped and drove his claws into his chest. In reality, Mysterio created an illusion that made Logan think they were all super-villains when they were actually his X-Men teammates. Wolverine realized he had sunken his claws straight into Jubilee and murdered her. Just before Jubilee died in his arms, she asked Wolverine why he was hurting her.
9 Cuts Off Cyclops' Eye
In the alternate version of Age of Apocalypse, Cyclops was getting pretty sick and tired of Wolverine always trying to steal his girlfriend, Jean Grey. The heated animosity between them continued even after Jean Grey ultimately chose to be with Logan instead of Scott Summers. Wanting to mark his rival's face, Wolverine decided to slash out one of Cyclops' eyes with his claws. Now only able to see with one eye, Cyclops would live the rest of his life with claw marks on the side of his face; a reminder of who defeated him.
8 Sexual Conquests
Logan lost all control after becoming possessed by demons in writer Jason Aaron's and artist Jefte Paolo's Wolverine: Wolverine Vs. The X-Men. The X-Men realize that the only way to bring back Logan is to enter his mind. Jean Grey, Emma Frost, Jubilee, Kitty Pryde, and Rogue discover what Wolverine really thinks of the female X-Men members. Boasting how he has managed to sleep with them, Logan only sees them as sexual conquests and ranks each one of them as lovers. Witnessing Logan's dark side, they wonder if their relationship ever mattered.
7 Stabs Rogue
In the first X-Men movie, Logan (Hugh Jackman) and Rogue (Anna Paquin) are out on their road trip when they end up being ambushed by the Brotherhood of Mutants. After being rescued by the superhero group, the two are allowed to spend the night and recuperate at Xavier's mansion. During the night, Logan finds himself haunted by his vague memories about the Weapon X Project. While Rogue attempts to wake him up from his nightmare, Logan opens his eyes and stabs her with his claws. Rogue ends up spitting out blood from her mouth after he retracts them.
6 Lord of the Vampires
In the pages of What If...?#24, writer Roy Thomas and artist Tom Morgan imagine what would happen if Wolverine became Lord of the Vampires. Dracula ends up taking a bite out of Wolverine's neck and transforms him into a vampire. Unfortunately, Dracula's hypnotism has no effect on Wolverine's mind. Because he cannot be mind-controlled, Wolverine strikes back and kills Dracula. After taking his place as the Lord of the Vampires, Wolverine drains the blood of the other X-Men members and turns them all into his vampire horde.
5 Earth X
In the dystopian future of the Marvel Universe, writer Jim Krueger and artist John Paul Leon imagined what would happen if everyone in the world suddenly had superpowers of their own. Because they are no longer special, Wolverine and Jean Grey have no more purpose in life. With his healing factor now worth nothing, Logan becomes a miserable and overweight drunk. Making sure her life is worse than his, Logan is horrible as a cheating and abusive husband to his frustrated wife, Jean Grey. As a married couple, they just want to kill each other.
4 Attacked Nightcrawler
In writer Chris Claremont's and artist John Byrne's Uncanny X-Men #143, Wolverine turns out to be a possessive control-freak when it comes to him and his love interests. While the other X-Men were celebrating the Christmas holidays at the X-Mansion, Wolverine decided to introduce everyone to his girlfriend, Mariko Yashida. As a prank, Kurt Wagner, also known as Nightcrawler, decided to score a kiss from Mariko. With Nightcrawler holding up a mistletoe, Wolverine immediately thought Mariko was cheating on him. Full of rage, Wolverine unleashed his claws and viciously attacked Nightcrawler.
3 Drunk Colossus
In writer Chris Claremont's and artist John Romita Jr.'s Uncanny X-Men #183, Peter Rasputin, also known as Colossus, was going through an awful break-up after Kitty Pryde dumped him. Though he supported Kitty's decision to end the relationship, Logan felt sorry for Peter and decided to help. Logan's advice for a heartache is to get wasted until the pain no longer hurts. The two end up having one too many drinks during their bar crawl. Wolverine decides to stay behind and watch as a drunk Colossus ends up in a brawl with the Juggernaut.
2 Punches Out Storm
Wolverine was having a difficult time dealing with Jean Grey's death. In writer, Chris Claremont's, and artist, Alan Davis', Uncanny X-Men #215, Wolverine and Storm, aka Ororo Munroe, decide to visit Jean's sister after her house burned down. While checking out the wreckage, Wolverine gets a whiff of Jean's scent and mistakenly thinks she is still alive. Storm struggles to convince Wolverine that he's wrong and gets punched out in return. Not only did Wolverine leave her unconscious on the floor, he actually lets her get kidnapped by the Marauders.
1 Left Cyclops To Die
In the Ultimate Universe, Wolverine has no love whatsoever for his X-Men team leader. He actually tried his best to kill Cyclops and get rid of all the evidence. In writer, Mark Millar's, and artist, Adam Kubert's, Ultimate X-Men #29, Wolverine had left Cyclops stranded in the middle of the Savage Land. Wolverine could have prevented Cyclops from falling into a chasm but he didn't. With his bones broken, Cyclops cried out for Wolverine's help but he was already gone. Four weeks later, Wolverine returned to the X-Mansion without Cyclops, letting everyone think he was dead.