Before I start, I LOVE ROCKY THREADS!

Here's my reasoning:

Mason Dixon wasn't all that dangerous. He came into the fight out of shape and took Rocky for granted.

Apollo Creed boxes circles around Rocky but I don't think he had the punching power to really be called "dangerous"

Ivan Drago and Clubber Lang were the two most dangerous IMO.

Drago was drugged up and a physical specimen. He had power and the ability to box but he was more of a robot trying to fulfill what was asked of him.

Clubber Lang was an ALL OUT slugger who didn't want to win the fight but wanted to actually hurt Rocky. He also had freakish power and he came forward looking to take your head off.

I think physically and punching power Lang and Drago were somewhat close. I think what seperates them was their mentality coming into the fight. In this case, my vote goes to Lang...