I'll admit I never beat Emerald ... I guess I just didn't train enough and I felt like beating the game then got sucked into 5 6 and 9. But it wasn't because he was any more hard than Ruby was even though I beat Ruby. I just was fighting him for the first time, I used Cait Sith's Slots and got a combo that instantly killed him, I'm not sure what it was. But yeah, I'm off topic, Ruby would win because he slaughtered my charas in 4 turns and I accidently out of desperation beat him with Cait Sith, where as it took forever for Emerald to even hurt me until he used that materia based attack and killed all of my charas, something that wouldn't work on Ruby.