How is Wolverine immortal?
Wolverine: Because of his healing factor, Wolverine is able to live longer than normal and show no signs of aging until a later period of time. X-23: Being Wolverine's clone, X-23 possesses the same healing factor and therefore has the same ability.
Meaning having been born in 1832, in a perfect world without Transigen and the Adamantium skeleton, Wolverine would have lived to the year 2298 at the age of 466. That's a long time, so much more longer than any of us.
Essentially, the answer to whether or not Wolverine can be killed with his healing factor is yes, but it's super, super hard to achieve. Short of suffocation or being completely annihilated by the sun, Wolverine is pretty much going to be able to handle anything he gets bombarded with.
Easy, he didn't. Wolverine was never immortal, it's a common misconception. Oxygen deprivation can kill him.
Wolverine's skeleton is coated in the indestructible metal adamantium, and it makes him nearly invincible. But without regenerative powers, Logan won't be the human wrecking crew he once was.
The typical longevity of a wolverine in captivity is around 15 to 17 years, but in the wild the average lifespan is more likely between 8 and 10 years.
Like having a skeleton coated in lead, the metal leeches into Logan's body over time. It takes years to have a major effect, but by 2029, the year “Logan” is set, the adamantium has so weakened Logan that he's aging at a normal rate and struggling to heal himself after injuries.
Wolverine died back in 2014, but fans will remember that in The Hunt for Wolverine, it was revealed the villain Persephone and her company Soteira stole his corpse from his grave. Now, in Return of Wolverine #5, we learn she brought him back to life and forced him to do black ops.
Unlike Wolverine, whose wounds sometimes cause excruciating pain as they heal depending on the severity, Deadpool has some degree of pain insensitivity. Deadpool is effectively immortal, although he has died several times. He is still alive 800 years in the future when the new X-Force encounters him.
Wolverine Gets Torn in Half by the Hulk
Wolverine #1, the Hulk wasted little time before ripping Wolverine in two and tossing each half of his body in different directions. To survive, Wolverine's top half had to literally crawl until he located the bottom half and let his body come back from that one.