Warning: contains spoilers for New Fantastic Four #3!
Marvel's Wolverine is often as much of a danger to his allies as he is to his enemies, and the X-Men's most popular member just killed a Fantastic Four teammate in a blind rage - but the man in question is surprisingly already dead. Logan rarely works well with others (thanks to his adamantium skeleton and healing factor that allows him to survive nearly every attack), but as a member of the X-Men from the 70s to the present day, he can be a team player when he wants. Unfortunately, in New Fantastic Four #3, the feral ferrous fighter foolishly faces the Fantastic Four's fiery Human Torch and kills him in battle...but his death doesn't seem to stick.
In current comics continuity, the new Fantastic Four (Spider-Man, the Incredible Hulk, Ghost Rider and Wolverine) form when each member independently thinks about traveling to Las Vegas. Ghost Rider believes dark magic is responsible for the four heroes pondering the exact same thought thought at the same time, and he's eventually proven right: Las Vegas is under attack by the demon Asmodeus. The four eventually encounter their greatest threat: a possessed Human Torch with no regard for their lives.
New Fantastic Four #3, written by Peter David with art by Alan Robinson, truly test the new team as Spider-Man dodges the Torch's attacks, but he fails to warn Wolverine who is subsequently hit by a demonic version of Ghost Rider's Penance Stare. Logan is compromised as he falls to the ground, horrified at all the people he's killed over the years. When he finally gets up, he's furious; Wolverine immediately unsheathes his claws and viciously stabs Johnny Storm in the back. "I said to wound!" Spider-Man shouts, but the Torch suddenly stirs moments after. "There's clearly something you aren't considering," he says as he rises from the ground. "You can't kill a dead man."
Clearly, Asmodeus has either already killed the Human Torch in the past - or this is not the Johnny Storm audiences know. Whatever the case, Wolverine displayed a shocking degree of violence when he stabbed his fellow crimefighter. It is possible - perhaps highly probable - that the vulnerability Wolverine showed after suffering from the Penance Stare drove him into even more of a murderous rage than usual, which led directly to the "death" of the Human Torch.
It must also be noted that Wolverine stabbed the Torch in the back in a sneak attack during the battle. While Wolverine is a more pragmatic hero and won't let a weakness like honor get in the way of a quick and easy victory, he also shows respect to his allies and friends. The fact that Wolverine decided to claw the Human Torch from behind shows he is truly incensed in this issue - and while he isn't exactly dead, he would have been were it not for Asmodeus' magic, and Wolverine should have exercised far more caution.