Who is the most violent "superhero"?
The Punisher is way up there, perhaps more than Wolverine...at least when Wolverine is hanging with the X-Men.
Very few characters are specifically written to be cold-blooded murders, yet still be considered heroes. But Frank Castle is and always has been. He's a good person who does things that he believes must be done for the sake of society.
Wolverine is an engineered assassin driven to extremes, in large part, by the experimental meddling done to him via the Weapon X program. In other words, he's a bit psychotic.
Punisher is not crazy and doesn't kill when he loses his cool. He intentionally choses to do what he does, and is perfectly sane and rational about it.
Deadpool is similar to Punisher in some ways. He doesn't get mad and start butchering folks. In fact he's often joking around during the carnage, but this demonstrates his disconnection is due to insanity. Plus he's a mercenary. So much of the time he's killing for a paycheck.
Punisher works for free. He is fulfilling a self-imposed duty to rid the world of criminals. He's not taking pleasure from his work and is not profiting from it. And although anger is his foundation, it's not an out of control impulse or rage. He just lives in a steady state mode of badassery.
So as far as Marvel goes, I nominate him as most violent superhero...although, now that I have written all this, I realized he's technically not a superhero because he has no super powers.
So, Deadpool I guess. I think his body count is higher than Wolvie's...