There's a possibility that it's one of his old enemies who has finally found a way to defeat him. Maybe they've discovered a weakness in Logan's healing factor or have a new weapon that can kill him. For example, if it's a foe who has studied him for a long time and found a way to disrupt his mutant abilities.
Perhaps he succumbs to an old wound or illness that has been haunting him throughout the story. In fanfiction, the author might play with the idea of his age finally catching up to him, and he dies a peaceful death in his sleep or while reminiscing about his life.
In the 'Old Man Logan' comic, Wolverine is presented as an older version of himself. His age is somewhat ambiguous, but it's clear he's past his prime and facing the challenges of old age in a dystopian world.
Well, the 'old man logan story' mainly focuses on Logan in his old age. It's set in a world where the superheroes have lost, and bad guys like the Hulk's in -bred descendants rule certain areas. Logan is trying to survive and protect his family. He has to go on a journey that forces him to confront his past and the new evils of this changed world.
I'm not sure exactly, but there are quite a few issues and related series. You might have to check with dedicated comic databases or fan forums for an accurate count.
The main character is Logan, aka Wolverine, in his old age. There are also villains like the in -bred Hulk family. And some other characters that Logan encounters during his journey in this dystopian world.
Old Man Logan's ending is quite intense. Logan finally faces his demons and brings some closure to his story, but it's not a straightforward happy ending.