Max level is 99.
Requires a turbo controller.
First set the buttons so that vertical attack (Y Button) is set to the A button on the remote.
Then go into Offline. Select Arcade and set difficulty to easy. Select Raphael.
Now however you have to, set your turbo control so A is getting pressed. I have a fight pad and used a rubber band to hold it down.
You will lose some battles but you will still get points so its all good.
Side note – the down side to this method is that since its an attack you get no movement credit even though Raphael will move forward during the attack so no cheap movement from this to get Wind of Battle.
Credit for this goes to my good friend Akulious. He is already level 99, using this method, just so he could unlock all the gear for create a character.
Please comment if voting poorly so I know how to improve my solution to gain your vote back.