Kingpin has already beat Cap. Luckily for Cap, Falcons hawk saved him, otherwise hed be dead.
To srank: I think it was a DD comic where Kingpin beat about 5 blackbelts. KP also benched a huge amount. Hes around Caps level if not at the level already. The most ive seen Cap bench was 1100 lbs. Kingpin can life that im sure.
Here's why... The Kingpin once fought the Red Skull in a Captain America comic. This was around the time that Cap had the super soldier serum removed from his body. Now, the Red Skull's body is cloned directly from Captain America's body. That means the Skull has a super soldier body.
The Kingpin and Skull fought at a baseball field. The Skull got some good shots off, but it really did not affect the Kingpin too much. The Kingpin won by literally falling over and and top of the Red Skull. The Skull was trapped by the Kingpins immense girth.
The Kingpin then threatened to jam his thumbs into the Skull's eyes unless he surrendered. The Skull did.
Now we have come full circle.
The Kingpin beat the Skull and I feel he would beat Captain America. Cap might be a slightly better fighter, but the Kingpin is no slouch. Plus he is so huge and damn strong.
That was a lot of writing.
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I am Lancelot of the Lake, and I have yet to find a king worthy of my sword!