Here's how I see the battle going:
Orochimaru would see Marth, and immediately "want his body" for um..."immortality" purposes. As soon as Orochimaru is about to..."absorb Marth's chakra," Marth would get a Smash Ball and Critical Hit Orochimaru off the stage into an explosion of light.
He who gets the Smash Ball usually wins. ...Unless they're terrible with it.
But then again, everything I wrote could be easily disproven by the fact that Orochimaru wouldn't want the body of such a prissy girl...
Orochimaru would see Marth, and immediately "want his body" for um..."immortality" purposes. As soon as Orochimaru is about to..."absorb Marth's chakra," Marth would get a Smash Ball and Critical Hit Orochimaru off the stage into an explosion of light.
He who gets the Smash Ball usually wins. ...Unless they're terrible with it.
But then again, everything I wrote could be easily disproven by the fact that Orochimaru wouldn't want the body of such a prissy girl...