Before starting, go into the game settings and change the Difficulty Level and turn Neutral Guard Off. You can also modify Life Gauge and Round Time if you'd like, but it's not necessary.
Select Original Mode > Team Battle to begin. You have to beat five teams of three opponents, all of whom are random except for third slot on the fifth team, which is Inferno. Select a team of three for yourself, choosing whichever characters you're familiar with. You can walk through it using Raphael by spamming 6 and throwing in the occasional and 3 for good measure, so you should put him on your team even if he's not your primary character.
Don't worry if you lose as there are continues.