User blog comment:Kaido King of the Beasts/A Rival for Luffy/@comment-4899461-20160119055128

If you want to talk rivals in OP, you gotta look at Gol D. Roger. He's got two documented rivals that fought on his level, Garp and Whitebeard. One Marine, one pirate. You only talk about Marines in this blog. So who is Luffy's pirate rival? There are a lot of returning villains in One Piece, but I think there's only one person capable of the kind of relationship that Roger and Whitebeard had. Someone that has literally been in the same boat as Luffy for the last couple years: Trafalgar Law.