Originally Posted by NewVincent
Now, there is another method that I am not really sure of that has a high chance of not working. For instance if you start off with one character, die and then as continue you end up finishing the game with a different one. I would imagine in that case it won't have the same effect. To be frank I have no idea how the game will consider it in the first place? Like starting with El Fuerte and his intro and finishing with Ryu and his ending :/ Dunno what that would cause :/
The method you are talking about definitely works. The person you finish it with counts regardless of if you change characters multiple times during arcade mode.
Lots of people will use the Zangief method (I did) because you can spam his lariat move and beat everyone with ease - you don't even have to look at the screen to know he will win.
So start with a character - lets say Ryu in order to unlock his opening cut scene (you need to watch all opening/ending cut scenes for a title or icon and ultimately the platinum). You can use him until you die or just purposefully die first match. Switch to Zangief and spam his lariat through all matches until you get to the Seth. Again purposefully die. Switch back to Ryu and try to beat Seth. If you do that will count as a completion with Ryu.
Rinse and repeat for all characters.