Streets of rage 2 is the best out of all the others, and out of final fight. I mean it had the best characters, Max, axel, blaz and skate. I was always axel or max, my friend was always skate, and the game was just great! When you double tapped an direction and hit an attack you'd do a different move (axel had the bare knuckle uppercut which, in japan, the games are called "bare knuckle"

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I mean, I played through final fight on the xbox capcom classics collection recently and it was monotonous, but streets of rage had different bosses, cooler bosses like Jet, and the guy who looked oddly like Blanka, and Shiva. The whole SoR trilogy is awesome. Streets of rage 3 is not without its charm either, especially since there's a code to be the kangaroo and to be shiva, but they gave skate some new special move where he flailed his arms running at the enemy, it was lame since the drill move was way better, but axel kept his fast punching one which was the best.
But yea, final fight was fun, but streets of rage destroyed it, and you can tell SoR 2 rips off final fight so much if you play the 2 games close together, cuz enemies look similar (punk rocker guys in SOR2 look like enemies in FF). Half the enemies even move the exact same way in both games. Either way, I have spent MANY hours in my life playing SoR games, but #2 was my all time favorite, hell, next to toejam and earl, Streets of Rage 2 is my favorite sega game of all time.