Both of them are badass no doubt, but who would emerge victorious? Personally I'd go for The Gladiator AKA The Spaniard than "THIS IS SPARTA!!!...... DUDE! (OK I admit thats a kick-ass line)
You mean the entire 300 vs the one Gladiator? If so the 300, of course! But if you mean Leonidas vs Gladiator. I'd still say Leonidas 'cause those Spartans don't fuck around, they're bred to kill.
Tuff choice i'm stuck between 300 with leonidas and Maximus put i have to say Leonidas he can take more hits then Maximus but i still love the movie Gladiator